(Photo credit: Dan Hamilton-Imagn Images)

Top-seeded Alexander Zverev, bouncing back after squandering two set points in the first set, rallied for a 6-7 (8), 6-4, 6-3 win over 18th-seeded Alexei Popyrin in the quarterfinals of the National Bank Open on Monday in Toronto.

The 28-year-old German advances to face either 11th-seeded Karen Khachanov of Russia or 26th-seeded Alex Michelsen of the United States in the semifinals. The latter two players faced off late Monday night.

Zverev is one match victory away from his fourth final of the season. He won the title at Munich, Germany, and wound up as runner-up at the Australian Open and at Stuttgart, Germany.

Following a first set in which Zverev failed on two chances to claim the tiebreaker, he established his dominance in each of the final two sets by jumping out to 3-0 leads.

Popyrin managed to pull level in the second set before Zverev broke again in the last game. The third set featured just the lone service break.

'I had to tell myself, even though I lost the first set, I thought we were both playing actually quite well,' Zverev said.

'I did one or two mistakes in the end (of the tiebreaker), and I was very unlucky with the net cord on set point. But all in all, I thought it was a high level, and if I continue playing that way, I'm going to get my chances -- and that's what I did.'

Popyrin finished with a slight edge in winners, 30-28, but that was more than offset by his 45 unforced errors. Zverev gave away only 30 points.

Zverev is headed to an ATP 1000 semifinal for the first time this year. He has seven career ATP 1000 titles, two of them coming last year in Rome and Paris.

--Field Level Media