The American was two games from defeat before recovering to win 6-7(2) 6-4 10-1 and draw World level at 3-3 with Europe in the overall score.
With two points available for a win on day two, defeat would have seen the red team looking down a 5-1 deficit with Nick Kyrgios up against Roger Federer next.
I wasn’t making any inroads on his serve at all and he was the better player for 85% of that match – John Isner
“Maybe we’re turning the tables just a little bit,” said Isner. “Team World is in this and we’re here to win, so let’s get it going!”
Zverev put himself in a commanding position with some fine serving, winning 20 of 21 points behind his first serve as he took the opening set on the tiebreaker.
An unexpected Isner double fault had handed the German the initiative and it took until the latter stages of the second set for the American‘s game to finally catch fire.
A lunging volley helped Isner grab the crucial break for 5-4, prompting his teammates and captain to leap to their feet, and the world No.20 carried the momentum into the match tiebreaker.
With his serve now firing and the groundstrokes in a groove, Isner dismantled Zverev 10-1, one blistering forehand winner down the line summing up the explosive change of circumstances.
“I wasn’t making any inroads on his serve at all and he was the better player for 85% of that match,” said Isner.
“Of course, I got a little lucky at 4-4 but once I got up 5-4, I had a lot of momentum, and I think I showed that in the tiebreaker.”
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