Hsieh and Mertens saved two match points in the second set and won 3-6, 7-5, 9-7. They clinched a back-and-forth third set when Hsieh hit a backhand winner to break Vesnina’s serve.
The Russian duo had two match points at 5-4 in the second set and also served for the match at 7-6 in the third.
Mertens also had a chance to serve out the match at 5-3 in the third.
Hsieh also won the French Open doubles in 2014. It was Mertens’ third Grand Slam doubles title and first at Wimbledon.