Fifth seed Alexander Zverev shrugged off a nightmare start to beat Borna Coric and book his place in the last four at the US Open.

Zverev showed few signs of form in the opening stages and trailed by a set and a break before rallying to overcome the Croatian 1-6 7-6 (5) 7-6 (1) 6-3 in almost three and a half hours.

In a match that rarely hit the heights, the decisive moments came in the fourth set when Zverev saved four break points before breaking Coric and ultimately serving out to take the match.