Felix Auger-Aliassime beat Denis Shapovalov 6-2, 6-3 in an all-Canadian third-round match at the Barcelona Open on Thursday.
The 10th-seeded Auger-Aliassime, from Montreal, saved the only break point he faced on the clay court.
The seventh-seeded Shapovalov, from Richmond Hill, Ont., could save only five of nine break points.
Shapovalov didn't appear to be at full health as a trainer looked at his shoulder during the match.
It was the third win in five career meetings against Shapovalov at the top level for the 20-year-old Auger-Aliassime. The Montrealer is now 2-0 on clay against the 22-year-old Shapovalov.
Auger-Aliassime was far more effective on serve. He won 78 per cent of points when he got his first serve in, 15 percentage points better than Shapovalov.