Americans Ben Shelton, Frances Tiafoe advance to US Open Round of 16

Shelton, the world No. 9, survived a demanding four-set battle with Canadaâ™s Denis Shapovalov, prevailing 7-6, 6-7, 6-3, 6-4.

The American initially surrendered his serve in the opening set before recovering, but Shapovalov regained control and moved to the brink of taking the set while serving for it.

However, the Canadian could not close it out, allowing Shelton to force a tie-break. Shelton then surged into a 5-1 advantage before sealing the opener 7-3.

The second set followed another dramatic pattern. Shelton broke early, only for Shapovalov to respond when his opponent attempted to serve for the set. Shelton restored his advantage, but another break from Shapovalov sent the contest into a tie-break, which the Canadian claimed 7-5.

Shelton finally established control in the third set with an early break and did not relinquish it, winning 6-3 before breaking again at the start of the fourth and protecting his serve to finish the job.

He will meet Stefanos Tsitsipas next, after the Greek defeated Jiri Lehecka earlier on Friday.

Tiafoe faced far less resistance against Monégasque player Valentin Vacherot, winning 6-4, 6-2, 6-4. He saved all three break points he faced and will next take on Daniil Medvedev. 

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