The likes of Liverpool, Manchester City and Chelsea are not far behind, though, and while the North London duo of Tottenham Hotspur and Arsenal have endured disappointing starts to the season, Matic is expecting them to be in and around the challengers too.
"It will be really tough winning this year, not only for us, but for all the teams. There are five or six clubs with a realistic shot at the title and have realistic hopes of contending," he told reporters.
"So it will be really difficult, but we all know very well that Manchester (United) has to play to win every single game, and there are plenty of games left to play. The Champions League hasn't started yet, we were drawn into a good group, with some quality sides, so we'll see what happens.
"I have become one of the more experienced players by now. At the age of 29 it's only normal that I wouldn't need a long time to adapt. I knew many of [Manchester United's] players from before, as I've played against them quite a few times, so I knew what kind of a team they are.
"And of course, the team helped me adapt quickly, they treated me very well from the very first day I entered the dressing room. The guys helped me adapt as soon as possible, and of course, on the pitch we also help out each other. So adapting was not a problem."
United are also one of only two teams - alongside newly-promoted Huddersfield Town - who are yet to concede a goal this season.