NEW YORK — Canada's Steven Diez is one victory away from his first main-draw berth at a Grand Slam after winning his second-round U.S. Open qualifier on Wednesday.

The Toronto player defeated Yosuke Watanuki of Japan 6-2, 5-7, 6-0 to advance to the final round of qualifying for the last major of the tennis season.

Diez, ranked No. 175, saved 4-of-6 break points and converted on 6 of 11 to knock out his 228th-ranked opponent.

The 28-year-old Diez will face No. 3 qualifying seed Soonwoo Kwon of Korea for the right to play in the main draw, which begins Monday. Kwon is ranked 90th in the world.

Diez's best career result at a Grand Slam was reaching the third round of qualifiers at the 2016 U.S. Open.

Peter Polansky of Thornhill, Ont., faces Sumit Nagal of India in a second-round qualifying match on Thursday.

If Polansky or Diez can advance through qualifying, it would would give Canada a record six players in a Grand Slam main draw for men's singles.

Montreal's Felix Auger-Aliassime, Thornhill's Milos Raonic, Denis Shapovalov of Richmond Hill, Ont., Vancouver's Vasek Pospisil and Brayden Schnur of Pickering, Ont., have automatic berths by virtue of ranking.

Five Canadian men played this year at Wimbledon, at the 2018 U.S. Open and the 1990 Australian Open.