In the first half Cardiff saw as much of the ball as their hosts, but were unable to test David De Gea, as Robin van Persie's early header put his side 1-0 up at the break.
United continued to control proceedings without being dominant and Ashley Young made sure of the points with a fine low strike from range in the 58th minute.
Read how the action unfolded with our live text commentary below.
6.47pmHello all and welcome to our commentary of Manchester United's clash with Cardiff City at Old Trafford. The points are important for both sides - United need to start to close the gap to the top four, while Cardiff are rooted at the bottom currently.
6.50pmUnited's fans will at least have seen signs that their team are intending to do something to claw them out of the situation they currently find themselves in. Finishing outside the top four was completely unheard of this season, but there's no doubt that their chances are boosted by the recent signing of Juan Mata.
6.54pmCardiff, too, have been busy in the transfer market as new boss Solskjaer looks to get the squad he wants to help in the relegation battle. Just today Kenwyne Jones joined from Stoke City in a swap deal for Peter Odemwingie, who joins Jo Inge Berget, Mats Daehli and Magnus Wolff Eikrem.
6.58pmThere is a fair bit resting on Berget, who Solskjaer knows well from having managed him at Molde. He has been talked up by the Norwegian boss and maybe we will see what he can do tonight. It will be interesting for sure. Especially now that I have the teams, so can let you know who plays.
7.01pmUNITED XI: De Gea; Rafael, Smalling, Evans, Evra; Valencia, Jones, Giggs, Young; Mata; Van Persie
7.06pmCardiff subs: Lewis, Turner, Kim, Eikrem, Gunnarsson, Daehli, Berget
7.09pmSo the big news then is that Juan Mata is straight in for his debut this evening. More of a surprise in that lineup, though, is that Robin van Persie is deemed fit to start having recovered from his injury. Wayne Rooney was expected to be fit and not RVP, but instead the Englishman is on the bench and the Dutchman leads the line.
7.12pmWith a midfield without Darren Fletcher or Adnan Januzaj starting, Mata has perhaps not the highest quality set of teammates around him tonight. With him operating behind the striker, David Moyes has gone for the solid Phil Jones as well as Ryan Giggs in the middle. On the flanks are Antonio Valencia and Ashley Young. There is a lot on Mata tonight.
7.15pmAs for Cardiff, well Berget will have to wait to get on as Craig Bellamy and Fraizer Campbell both play tonight. It will probably be a solid three in the middle when not in possession, with Gary Medel and Peter Whittingham deeper than Jordon Mutch and Craig Bellamy operating from the flank to cause general trouble. Campbell has an important role today leading the line.
7.19pmIn terms of the record between these two sides it does not look good for tonight's visitors. They have to go back to 1960 for their last win in this fixture, which was a 3-0 victory at Ninian Park in what was then Division One. Of course, they haven't been in the same division for many years now.
7.23pmIn all, the teams have met 13 times in league encounters with the Bluebirds having one just one other. That was in 1954 at Old Trafford, so can they manage it nearly 60 years later? You would have to fancy United tonight, despite their relative woes, as on paper they should have too much for Cardiff.
7.27pmThere's an interesting facet to this one tonight - for United fans, anyway. If the Red Devils can win tonight they will be the first Premier League team to reach 1,000 points at home. The tally is currently at 998, so a draw would leave it agonisingly close. Solskjaer came off the bench to have a say in a bunch of those 998 but he'll want to make sure it stays there for one more night.
7.33pmCardiff have made themselves at home in Greater Manchester recently. This is their third game in a row in the area in little over a week, following the 4-2 defeat to Manchester City and 1-0 FA Cup win at Bolton Wanderers. Campbell scored in both those games and is beginning to hit a little bit of form. Can he keep it up?
7.36pmTonight's visitors will certainly be looking forward to a return to Wales, especially when you look at their recent record away from home. In their last eight league games away, they have lost six and won none. There's little surprise, looking at that form, why they are currently stuck to the bottom.
7.40pmA look at the odds pre-match tells us that the bookies are not expecting Cardiff to end their poor run of form tonight. United have moved to 2/9 from 1/4 - presumably now that the teams have been confirmed - while the away side are 16/1. I would be very surprised, but Cardiff did play well against City and United are not as strong as their neighbours.
7.43pmPREDICTION: I think this will be quite close, but I do expect United to have too much in the end. I can see it being level at the break, but the hosts to go on to take it 2-1.
1 minKICKOFF: Here we go then, the hosts get things started kicking from right to left.
2 minEarly corner for United, which Young takes, but it's too lofty and is easy for Marshall to rise and gather. Decent start with the ball from United.
4 minSomething of a chance there for Cardiff, as they looked to break from a poor pass by Smalling. It goes wide to Mutch, but he's closed down and is only able to cross to a red shirt and the ball is cleared.
6 minMata has the run of the United midfield at the moment - he's coming very deep to get involved. One such occasion he drills and angled ball wide to Evra, who then finds Young. His cross is first headed on to the bar by Valencia, then RVP's follow-up effort is saved before he finally heads in the opener.
8 minThe hosts are in command at the moment and it really looks like they could score at will. Evra stays up field and has another chance to cross, but this time it's hacked clear before reaching Van Persie. Moyes will be delighted with his side's start.
11 minThe passing is neat and crisp from United at the moment, but really they're being given too much time on the ball. Cardiff's game hasn't quite got going and certainly the early goal will have been a blow to their aim of keeping things tight to begin with. It worked against City, but hasn't tonight.
13 minCardiff have just come into it a little bit more over the last few minutes. First Campbell takes a ball well into his path, but is shepherded by Smalling, before a ball over the top is too far for the striker to get on to.
16 minGood spell of possession football for Cardiff here, probably their best of the game so far. However, they cannot create a chance from it and United have it back.
18 minThe final pass has not been right so far for Cardiff. Too often they've tried the direct ball into the flanks, but with only Noone and Campbell running between the lines it's leaving too much for them to do.
20 minCHANCE! Good work from Giggs to win the ball back in midfield. From it the ball is clipped into the far post by Mata, but Young sliding in cannot make contact. I think he should have done - that was a chance.
22 minBOOKING: Cardiff have given away a couple of free kicks recently. Noone escapes with an accidental elbow, but Bellamy goes into the book for catching Valencia late. Mata puts the ball into a good area but Evans can only glance his header wide.
25 minYoung has played really well so far, and that's more good work down the left. He passes short to RVP, who beats McNaughton and puts in a cross, but there's no-one in the box and Marshall can gather easily.
28 minNot too much in the way of action in the last few minutes as Cardiff try to keep hold of the ball and slow the game down somewhat. United have seen most of the ball, but despite that have only had a couple of really good chances. Cardiff are certainly still in this.
30 minCampbell tries to flick the ball round the corner against Smalling and race on to it, but the centre-back shows good pace himself to get between the striker and the ball and win a free kick.
33 minCLOSE! United up the pressure a little again and win a throw followed by a corner. Young, who has crossed well so far, will take this one. It goes short and is worked into the box, where RVP strikes wide of the far post from the narrowest of angles. Close.
36 minWhittingham is coming ever deeper to get himself involved in the game. As yet he's had little success with his sprayed passes to the flanks and that's largely down to Jones coming into the middle when United are off the ball to allow the centre-backs to cover more width.
38 minGiggs drives forward for one of the first times in the match so far, but his cross from a narrow position is headed away. Jones picks it up and shoots from range, but it's blocked and away to safety. The early United creativity is lacking a little at the moment.
40 minFirst thing that De Gea has really had to do in the game so far, and he was far from convincing. John's cross from the left is just too deep, but the keeper can only turn it behind for a corner. His positioning was all wrong there.
43 minEvra goes to ground as Noone comes in for a tackle, but there aren't any appeals as the left-back just slipped going for the cross. It's quite even at the moment.
45 minMata has put in plenty of crosses from quite narrow positions today. The latest effort is easy for Marshall and Cardiff break, but Bellamy's pass to Campbell is woeful and goes out for a goal kick.
45+1 minHALF-TIME: Manchester United 1-0 Cardiff City
8.32pmSo far, so good for United, but this one is far from over. They got the perfect start with a goal for RVP after six minutes, but despite a lot of possession they've not had many further chances to really extend the lead.
8.36pmCardiff have yet to properly test De Gea, but what they have done is keep things very tight when off the ball and have frustrated United to a large extent. There's absolutely no reason while it remains 1-0 that they cannot nick a goal.
8.39pmYoung and Mata have played very well so far in support of their lone forward. Mata has been very keen to impress; dropping deep and getting balls into the box whenever possible, while Young has been excellent with his crossing and drifting into space.
8.43pmA quick look at the stats then, and there's some interesting reading. In terms of the possession it's 50% each - which is a bit of a surprise, as Cardiff have done nothing with their share. It's seven shots to four in favour of the hosts, and two to none on target. You can't help but feel with a dominant central midfielder United would be racing ahead here.
8.46pmThe players are coming back out now. United ended that half with too much sideways passing and will need to revert to how they played at the start of it.
46 minSolskjaer's men - who is currently getting a big reception from the United crowd - kick us off for the second half.
48 minNeither side has taken control of the half yet, and Moyes doesn't look too pleased with his side at the moment. Cardiff look likely and are pressing a bit higher up the pitch at the moment.
51 minThat would have been a chance for RVP, but Valencia's cross to him was just slightly behind. He tried to keep it back in play with a flick back but the chance was gone. Good work to set Valencia away, but he has to cross better in that situation under little pressure.
53 minStill Cardiff are playing on the break, but another pass over the top to Campbell by Bellamy leaves the striker with too much to do. The next goal is very improtant here.
55 minCHANCE! Big chance there! John's cross from the left just needs to be turned in by Campbell, but he slipped and then Evra beat Kim to the ball afterwards. John had so much room down the left.
58 minThat's a fine solo effort from Young! He cuts in from the left flank and absolutely rifles a low drive into the bottom far corner. Unstoppable.
61 minThat has brought Old Trafford to life! It probably will be the win now, but they must make sure not to concede in the next 10 minutes as Cardiff will probably come at them.
63 minUNITED SUB: On comes Wayne Rooney, but instead of partnering RVP he comes on for the Dutchman.
65 minEvans tries to take a leaf out of Young's book and shoots from almost an identical position. His effort goes some way wide of the post, though.
68 minFerguson in the stands looks more interested in his phone than the pitch at the moment, as Hudson comes off for Ben Turner. Straight swap at the back for Cardiff there.
70 minUnited have been very solid at the back in this half, as Rafael manages to hold off Kim and win the ball back. It's still all long-ball stuff in the final third from Cardiff and they've had no joy so far.
72 minCLOSE! Rooney doesn't want to miss out in the long-range strike stakes, and goes for goal around 25 yards out. It hits Caulker, which almost takes it past Marshall but it goes just wide.
74 minOFF THE POST! Close from Valencia. He's played in and initially it looks as though the chance has gone as he cuts on to his left, but he does eventually shoot and Marshall manages to push it on to the post. Good stop.
77 minCardiff are enjoying a spell of possession here, but they have really had no way through the United defence so far. The passing is all sideways until the eventual pass into the channel. On come Daehli against his old club for Noone.
80 minCHANCE! Mata might well have been celebrating a debut goal there, but he cannot get enough on Evra's cutback at the near post and it's blocked away. Cardiff escape.
83 minThere's not a great deal of pace to this any more, although in fairness there hasn't really been throughout. United can see this out now without too much effort I would think.
84 minUNITED SUB: It wasn't a spectacular debut, but more than good enough from Mata. He makes way for Adnan Januzaj.
88 minCardiff are huffing and puffing, but they haven't had nearly enough quality to get anything out of this one tonight. One defeat doesn't tell us too much, but they could really struggle to stay up.
90 minCHANCE! Januzaj probably should have scored there. Rooney plays in Evra down the left, but from his pull-back he rolls the shot wide. Poor miss, really.
90+1 minWe're into the first of four added-on minutes.
90+3 minCLOSE! Decent attempt from Rooney, who tries to curl one into the far corner from just outside the box, but his shot goes not too far wide.
90+4 minFULL-TIME: Manchester United 2-0 Cardiff City
9.38pmIt's a relatively straightforward win for United tonight then, who managed to beat Cardiff without having to play too well.
9.39pmMata had a decent debut, RVP looked good as ever and the performance of Young was encouraging. That's all from me for this one, but please hang around on site for all results, reaction and analysis from tonight's football. Goodbye.