Pakistan, Aug. 2 -- Top seed Alexander Zverev switched into survival mode to claim a milestone 500th ATP match win on Thursday, fighting back to beat Matteo Arnaldi 6-7 (5/7), 6-3, 6-2 at the Toronto Masters.

Germany's Zverev broke twice in the deciding third set to reach the fourth round of the US Open tuneup, converting his second match point to back up his defeat of the Italian ealier this year in Acapulco.

"It's a great achievement," Zverev, winner of 24 ATP titles, said of reaching 500 career match wins. "Not a lot of player reach this milestone.

"But I still want 500 more - maybe even more," he joked. "You always want to win as many matches as possible. I'm all about this."

Unable to gain the upper hand in an 82-minute first set...