It was Del Potro who was triumphant over the home favourite in Basle, but Federer soon went about exacting some revenge as he broke the Argentine early in the opener on his way to establishing a one-set lead.
The 17-time Grand Slam champion lost only two points on serve during the first set, and continued to serve imperiously throughout the second, until the 10th game, where unforced errors gifted Del Potro the break which levelled the contest.
There were to be three consecutive breaks in the middle of the decider, with Federer claiming two of them and going on to record a 6-3 4-6 6-3 victory which sets up a semi-final meeting with Novak Djokovic.
Below, you can read how the action unfolded in France.
2.50pmThe action never stops for long at the Paris Masters. We have just witnessed a Novak Djokovic masterclass, and now we are in for another instalment of high-quality tennis - Federer vs. Del Potro.
2.52pmFederer will be looking to exact some revenge on the Argentine for his defeat in Basel last week, and also to prove a point following a poor record against the world's other top players this season.
2.54pmThe Swiss maestro has only beaten one of his fellow competitors in next week's ATP Tour finals all year - a victory over his compatriot Stanislas Wawrinka at Indian Wells way back in March.
2.58pmPREDICTiON: I expect Federer to gain a confidence-boosting win here. Del Potro has beaten the 17-time Grand Slam champion on three successive occasions. Not many people, if anybody, has got the better of the great man four times in a row. I'll plump for Federer in three.
Federer 1-0* Del PotroFederer wastes little time in getting himself on the scoreboard with a rapid service game. He holds to love in less than a minute and strolls with confidence to the other side of the court.
Federer *1-1 Del PotroDel Potro's opening service game is nowhere near as easy, as he is forced into saving a break point and take the scores to deuce. Federer produces some good defence to stay in the game, but the Argentine eventually powers his way to an important hold.
Federer 2-1* Del PotroThe Swiss maestro just makes it seem so simple at times. He drops just one point on his way to going 2-1 ahead, and that slick and classy serve of his is looking as effortless as ever.
Federer *3-1 Del PotroBREAK! An early break for Federer, who forces Del Potro into a couple of unforced errors and then takes his break point at the first opportunity.
Federer 4-1* Del PotroFederer is known to be one of the great frontrunners in tennis, and the way that he is serving in the early stages of this contest make a Del Potro comeback in this first set appear highly unlikely. He moves three games clear in the opener with a delightful backhand slice which spins away from the Argentine. His 11th winner already.
Federer *4-2 Del PotroThis is as good as we have seen from Del Potro so far in this contest, as he runs around the ball to power a forceful forehand down the line and beyond Federer on his way to holding.
Federer 5-2* Del PotroFederer replies to Del Potro's superb winner in the last game with some brilliant strokeplay of his own, in the form of his famous one-handed backhand, which he sent crosscourt into the corner. This game has moved at a startling quick pace, and now Del Potro is serving to stay in this first set.
Federer *5-3 Del PotroThere is a sniff of a set-winning break for Federer at 15-30 on the serve of the Argentine, but a long forehand from his opponent, and then a superb flurry of wristy forehands helps Del Potro fight back, and forces Federer to serve for the opener himself.
Federer 6-3* Del PotroSET! Federer serves out for the set like a man who has done it 1000 times, which he actually has. It took the Swiss just half-an-hour to win the opener, which he did having conceded just two points on his own serve, and having struck 17 winners.
Federer *6-3 1-0 Del PotroOnly once has Del Potro come from a set down to beat Federer in their 18 meetings, and that was at the US Open final in 2009. He gets off to the best start in trying to repeat that by holding in the opening game of the second, where we saw the first real prolonged baseline power exchange, which the Argentine came out on top of. There were a few errors in there as well, which forced him to deuce, but he corrected those in the end.
Federer 6-3 1-1* Del PotroDifferent set, same story for Federer, who has been as untroubled as you could possibly imagine on serve thus far. He is irritated with himself for faulting with the score at 40-15, but Del Potro cannot seize this slimmest of openings, as he thumps his forehand return to the second serve into the net.
Federer *6-3 1-2 Del PotroA subtle change of pace from Federer brings Del Potro into the net and his attempted passing winner flies off the frame and into the crowd. That puts the Swiss 30-0 clear, but some thunderous baseline hitting helps the fourth seed reel off four points in a row and claim a come-from-behind hold.
Federer 6-3 2-2* Del PotroFederer drops the ball just over the net from the front of the court and then turns away assuming he has won the point, which he had, as Del Potro steamed in towards the net before pulling out of the shot, and instead jumping over and joining Federer for a light-hearted exchange! The Swiss holds to love for the fourth time in this match.
Federer *6-3 3-2 Del PotroDel Potro keeps this second set on serve, and again demonstrates that he may have the advantage if the rallies become longer and are played from the baseline. Promising signs for the Argentine, but he looks no closer to breaking Federer.
Federer 6-3 3-3* Del PotroAs proven in the latest Federer service game, as the 17-time Grand Slam champion only allows his opponent one point before securing another comfortable hold, courtesy of some excellent combination play, following up wide serves with crosscourt forehands on two occasions.
Federer *6-3 4-3 Del PotroSome good combination play also on display here from Del Potro, who sends Federer wide and then comes into the net before wrong-footing the Swiss, who was sprinting back across court, with a forehand in the opposite direction. That sets the tone for a comfortable hold.
Federer 6-3 4-4 Del Potro*A wasted opportunity on the first point of the game from Del Potro, who struck the net chord with a fairly easy forehand, allowed Federer to again serve without pressure, and without dropping a point, on his way to levelling this second set once more. We look destined for a tiebreak from where I'm sitting.
Federer *6-3 4-5 Del PotroGood judgement from Del Potro, who calls for hawkeye from a Federer backhand and gets the benefit of the challenge by the smallest of margins. There was no element of luck in the way that he secured the game, though, with an unstoppable forehand that thumped into the advertising hoardings. For the first time there is now pressure on the Federer serve, as he attempts to stay in this second set.
Federer 6-3 4-6* Del PotroBREAK, SET! Del Potro wins the opening point with a superb crosscourt return on the stretch, and a few points later, Federer sends a wild, unnecessarily attacking forehand wide to hand the Argentine his first break point opportunity. Federer saves, but only temporarily though as another forehand error gifts Del Potro the set which levels this match. That is what pressure does!
Federer *6-3 4-6 0-1 Del PotroDel Potro kicks off the deciding set with an ace down the middle, and then follows that up with a brilliant forehand winner, down the line on his way to holding to 15.
Federer 6-3 4-6 1-1* Del PotroThere is a sign that the tide may be turning in this match when a Del Potro forehand hits the top of the net twice and lands on the Federer side. Had the Argentine got the better of the long rally that followed in the next point, he would have had a real opening at 0-30 on the Federer serve. As it was, the world number five thumped a forehand into the net, and Federer did the rest, winning the next three points.
Federer *6-3 4-6 2-1 Del PotroA perfectly-judged Del Potro flick from Federer's deep forehand forces the Swiss to come forward, and he can only succeed in slicing his backhand into the net. Del Potro holds to 15 for the fifth time in a row.
Federer 6-3 4-6 2-2* Del PotroFederer levels the set up at two apiece in a game full of remarkable shots! The seven-time Wimbledon champion started things off with a rasping ace down the middle, and he established a 40-15 lead thanks to a well-taken overhead. Del Potro responds with an 168kmph return winner that has the crowd purring, but is not enough as Federer hangs on.
Federer *6-3 4-6 3-2 Del PotroBREAK! This could be the decisive break in this counter, and it is a break to love from Federer. The Swiss maestro firstly surprises Del Potro by hitting a passing winner down the line, when the Argentine was expecting him to hit crosscourt, which he did during the next point for another forehand winner. Del Potro has no response, and folds tamely with two errors into the net.
Federer 6-3 4-6 3-3* Del PotroBREAK! A fantastic crosscourt winner from the fourth seed helps him break back at the first opportunity. This is where the Del Potro of 2013 differs from that of 18 months ago. He truly believes that he belongs at the top table and never surrenders after going behind.
Federer *6-3 4-6 4-3 Del PotroBREAK! A third break in a row gives Federer the advantage once more! The Swiss missed a volley by inches at 0-30, but Del Potro followed suit the point after by failing to control his shot from the net following Federer's forceful forehand. A tired shot into the net from Del Potro gifts his opponent the game, and this time, there may not be a way back.
Federer 6-3 4-6 5-3* Del PotroFederer is on a roll now as he moves Del Potro around the court with ease, before putting him away with an emphatic smash. The Swiss holds to love and is now one game away from another Paris Masters semi-final.
Federer 6-3 4-6 6-3 Del PotroGAME, SET, MATCH! There was to be no stopping Federer after that break in the seventh game, and he has secured his passage into the last four with a third straight victory on the Del Potro serve. That's an important win for the 17-time Grand Slam champion, as it is the first one against an opponent ranked in the top 5 this season
4.48pmThat will give the Swiss confidence heading into London next week, but he did not play as if he was short of it today. He first set performance was resemblant of the Federer of old, and if he can reproduce that sort of display against Djokovic in the semi-final, he is in with a real chance against the world number two, who was equally impressive earlier this afternoon in his triumph over Wawrinka.
4.50pmThat's it from me for this afternoon. Thanks for joining me to witness Djokovic and Federer near their best. When they are, there's not many better sights in sport! Who will make up the other semi-final? Be sure to tune in to SM later this evening for live coverage of the other two last-four matches from Paris.