The Shenzhen Open top seed Alexander Zverev has exited the event. The 20-year-old fell short to an in-form Damir Dzumhur in the quarter-finals. The world No. 40 needed just two sets to beat the German 6-4 7-5. It was the first-ever meeting between the two.

The favorite Zverev got off to a good start. The world No. 4 opened the match with a 2-0 lead. Then unexpectedly, Dzumhur won four games in a row to open up a 4-2 lead. No more breaks were seen as the No. 6 seed held on to his serve to win the opener.

Zverev regrouped at the beginning of the second set.

The No. 1 seed seemed to be cruising to a decider as he had a 4-1 lead. But, yet again, Dzumhur found his way back, making it 4-4.

Zverev managed to stop Dzumhur's run by winning the ninth game. The German was on the brink of winning the set in the following game. The resilient Dzumhur saved three consecutive set points to make it 5-5.

Zverev was then brutally punished by Dzumhur. The No. 6 seed took the decisive break to open up a 6-5 lead. The Bosnian served out for one of his biggest wins ever in the following game.

Zverev falls to convert his break point chances

Dzumhur came up clutch when needed most in the quarter-finals of the Shenzhen Open. The No. 6 seed converted 4-of-7 of his break point chances against Zverev.

On the other side, the Bosnian saved 5-of-7 of Zverev's break point opportunities. Just in the second set, the No. 1 seed realized 1-of-6 of his break point chances. The match came to an end after an hour and a half of action.

Dzumhur plays Dolgopolov next

Dzumhur is now set to meet No. 5 seed Aleksandr Dolgopolov in the Shenzhen Open semi-finals.

The Ukrainian had 6-3 4-6 1-0 lead when Israel's Dudi Sela retired the match. Dolgopolov missed an opportunity to get the job done in straight sets. He had a break point in the ninth game of the second set -- which he didn't convert. Sela ended up winning that and the following game to force a decider -- from which he retired, eventually.

Dolgopolov and Sela met for the first time in six years. Back in 2011, Sela defeated Dolgopolov at the St. Petersburg Open. The outcome of the match was different in their second matchup.

Dzumhur and Dolgopolov have no previous meetings. Dzumhur is coming off a winning St. Petersburg Open campaign. The Bosnian will certainly be eyeing to reach the final and potentially win back-to-back ATP titles. However, beating Dolgopolov won't be easy, as the Ukrainian has lost only one set so far this week in Shenzhen.