Mauricio Pochettino hailed hat-trick hero Kylian Mbappe as "one of the best players in the world" after the Frenchman helped Paris St-Germain to a 4-1 win against Barcelona in the Champions League. The 22-year-old helped carve out a big advantage in the first leg of the last-16 tie, equalising after Lionel Messi opened the scoring and then netting twice more. Moise Kean was the other scorer in a superb night for Paris but Pochettino, seven weeks into his spell at the helm of the Ligue 1 side, tried to keep his side grounded. "There are 90 minutes left and they have great players. There's still a second leg," he told the Uefa website. "Perfection doesn't exist. I'm happy with the result and performance, but we have to stay humble. We have a big match against Monaco on Sunday and we're already thinking about that." On Mbappe, the former Tottenham boss said: "There's no doubt that Kylian is one of the best players in the world, despite his young age. He's already done extraordinary things, but we have to stay humble." The result leaves Barca requiring another considerable comeback heading into the second leg at the Parc des Princes on March 10, four years on from the sides' memorable last-16 clash in which the La Liga outfit recovered from a 4-0 first-leg loss in France by winning the second 6-1 at Camp Nou. For what was the first meeting since then, Barca's line-up included Gerard Pique, returning to Ronald Koeman's defence after almost three months out due a knee injury. Ousmane Dembele was also among the players coming in as he joined Messi and Antoine Griezmann in the attack. PSG, with former Barca man Neymar and Angel Di Maria still sidelined, started with a front three of Mbappe, Mauro Icardi and Kean. Barca grabbed the lead in the 27th minute after referee Bjorn Kuipers pointed to the spot when Frenkie De Jong went down in the box under pressure from Layvin Kurzawa. Messi fired the resulting spot-kick high into the net for his 10th goal in 10 games in all competitions. Mbappe drew things level in superb style five minutes later, collecting a flick from Verratti, dancing around Clement Lenglet and rifling the ball past Marc-Andre Ter Stegen. PSG then went 2-1 up in the 65th minute when Alessandro Florenzi crossed from the right and the ball went via a touch off Pique to Mbappe, who lashed it in. Shortly after, Mbappe was denied a hat-trick when he saw a low shot blocked by Ter Stegen before Kean made it 3-1 as the on-loan Everton man connected with Leandro Paredes' free-kick. Mbappe's third did arrive in the closing stages as PSG broke forward and the 22-year-old star curled a shot past Ter Stegen having been teed up by Julian Draxler. Barca coach Ronald Koeman said: "I could tell you lies but the fact is that at 4-1 down from the home leg, there are very few chances of going through. "This match shows us how much we have to improve, particularly at Champions League level."