TORONTO -- Canadian wild card Felix Auger-Aliassime upset Lucas Pouille of France 6-4, 6-3 at the Rogers Cup on Tuesday, cruising into the second round in his main draw debut at the Masters 1000 tournament.

The Montreal native, ranked a career-high No. 133 in the world heading into the week, needed one hour 18 minutes to down the No. 18 Pouille on centre court at the Aviva Centre.

Auger-Aliassime, on the eve of his 18th birthday, saved 5-of-6 break points and converted on 3-of-6. He also fired five aces -- including four in the second set alone -- and won 73 per cent of his first service points.

The teen started strong, breaking Pouille in the second game of the first set, then fighting off triple break point for a 3-0 lead.

Pouille broke the Canadian while he was serving for the set at 5-3, but Auger-Aliassime bounced back with another break for set point, letting out an approving roar as fans waved Canada flags in the seats.

Auger-Aliassime converted on another break point in the second set and held serve the rest of the way to secure just his second career win at a Masters 1000 event.

He will face Russian qualifier Daniil Medvedev in the second round. Medvedev upset 13th-seeded American Jack Sock on Monday.

Auger-Aliassime won his first at Indian Wells back in April, defeating fellow Canadian Vasek Pospisil in the opening round to become the first player born in the 21st century to win a Masters-level match.

Auger-Aliassime lost in the qualifying round at the Rogers Cup in Toronto in 2016 and had to withdraw his wild card entry to the 2017 tournament in Montreal with a left wrist injury.

Auger-Aliassime began the year ranked 161st.

Earlier Tuesday, four-time champion Novak Djokovic advanced to the second round with a 6-3, 7-6 (7) win over lucky loser Mirza Basic, and former world No. 3 Stan Wawrinka came back to beat 16th-seed Nick Kyrgios 1-6, 7-5, 7-5.

Djokovic, the ninth seed in Toronto, took care of his serve in the win over his Bosnian opponent. Djokovic had nine aces and was good on 76 per cent of his first serves, converting 76 per cent of his first service points and 79 per cent of his second service points.

He had some trouble late in the second set, losing his serve to set up the tiebreak, before rallying back.

The Serbian star, who last won the Rogers Cup in 2016 and is coming off a win at Wimbledon this year, will next face wild-card Peter Polansky of Thornhill, Ont.

Wawrinka, a three-time Grand Slam champion, came into the tournament ranked 195th in the world as he looks to get back into form following knee surgery.

The Swiss player was originally given a qualifying spot in Toronto, but advanced to the main draw when former No. 1 Andy Murray withdrew.

Kyrgios, from Australia, broke Wawrinka twice in the first-round match and had seven aces in a dominant first set.

Wawrinka battled back, converting on 86 per cent of his first service points to take the second set. He broke Kyrgios in the final game of the third set, converting his second match point opportunity when the Australian couldn't handle his return.

"Stan, for him to get through matches like this, healthy, no pain, that's a good sign for him," Kyrgios said. "He's playing a good level. He's got a world-class backhand and matches like this are going to give him confidence.

"But I can't take any positives away from this at all."

In another first-round upset, Robin Haase of the Netherlands downed Japan's Kei Nishikori 7-5, 6-1. Americans Sam Querrey, Frances Tiafoe and Ryan Harrison joined Russia's Karen Khachanov and Greece's Stefanos Tsitsipas as other first-round winners. Tiafoe will face Milos Raonic of Thornhill, Ont., in the second round.

Denis Shapovalov of Richmond Hill, Ont., played his first-round match against France's Jeremy Chardy later Tuesday.