Flummoxed and frustrated by wily veteran Paolo Lorenzi for two sets, second seed Andy Murray changed tactics and beat the 34-year-old Italian at his own game to advance to the US Open fourth round.
Murray was moping and muttering to himself as he pressed for winners against the steady Italian and piled up unforced errors before deciding to patiently play long rallies that enabled him to secure a 7-6 (7-4) 5-7 6-2 6-3 win.
World No.2 Murray committed 47 errors in the first two sets, including 31 off his forehand, and converted only four of 12 break points before finding his form in the third set.
The 40th-ranked Lorenzi put up a gritty fight despite coming off a gruelling five-set, five-hour win over French 30th seed Gilles Simon in his second-round tilt.
The Scotsman’s harder than expected three-hour 17-minute victory kept his golden summer moving forward after triumphs at Wimbledon and the Rio Olympics.
“I stopped rushing in the rallies,” 2012 US Open winner Murray said.
“I was making quite a few unforced errors.
“He’s an extremely solid player and doesn’t give you many cheap points. I was trying to get cheap points, I was going for too much.
“When I slowed things down and waited for the right shot to go for, my unforced errors went down, the winners went up and the scoreboard started working in my favour as well.”
Murray advanced to a fourth-round clash with 22nd seed Grigor Dimitrov of Bulgaria, a 6-4 6-1 3-6 6-2 winner over Joao Sousa of Portugal.
Eighth seed Dominic Thiem was serenaded by the crowd as he celebrated his 23rd birthday with a gruelling 1-6 6-4 6-4 7-5 victory over Pablo Carreno Busta of Spain.
The Austrian was pushed hard, especially in the fourth set, but held on to seal a victory which was followed by a rendition of Happy Birthday by the Grandstand Court fans.
When former US Open champion Juan Martin del Potro began his latest comeback in March he said he was playing for fun after three operations on his wrist.
Six months on, with an Olympic silver medal in the bag, the Argentine beat 11th seed David Ferrer of Spain 7-6 6-2 6-3 to reach the US fourth round for the first time since 2012.