Ben Shelton booked his place in the Canadian Open semi-finals with a straight-sets victory over Jakub Mensik.

The defending champion won 6-3 6-1 in an hour and 14 minutes, with the American yet to drop a set in the competition this year.

It was a clinical first set from Shelton, who converted his only break-point opportunities in the fifth and ninth games to win the set, while also winning 88% of his first-serve points.

And Shelton maintained his momentum in the second, where he raced into a 5-0 lead after converting two of his four break points before clinching the win with his first match point.

"It felt great," Shelton said after the victory. "To be honest I was really happy with my return game, the way that I played from the ground from point one for me is where I want to be at.

"I think that the level that I maintained throughout the match was really high and if I was nitpicking at all, it was just the way I served at the end.

"I kind of lost the rhythm on my serve, but I’m super happy with the way that I played tonight and the performance I came up with. I hope to continue and build on these things in the semis."

2 - Ben Shelton is now the fourth player in the past decade to reach his first two ATP Masters 1000 SFs at the same event after Nick Kyrgios (Miami), Diego Schwartzman (Rome) and Taylor Fritz (Indian Wells). Capitalise.#OBN26 | @OBNmontreal @atptour pic.twitter.com/yeCo9tgX7k

— OptaAce (@OptaAce) August 11, 2026

Shelton will face compatriot Learner Tien in the semi-finals after the latter's 6-3 6-2 win over Daniel Merida.

Shelton continues to shine in Canada

Shelton is now the fourth player in the past decade to reach his first two ATP Masters 1000 semi-finals at the same event after Nick Kyrgios (Miami), Diego Schwartzman (Rome) and Taylor Fritz (Indian Wells).

He is also the first defending champion at the Canadian Open to reach the last four since Rafael Nadal in 2019, with 2024 winner Alexei Popyrin and 2023 champion Jannik Sinner both falling in the quarter-final stage of their title defences.

Shelton now faces a tough test against Tien, who has reached his first Masters 1000 semi-final.

Tien has won both previous career meetings against Shelton, defeating him at Indian Wells 2026 and Mallorca 2025.