Vandeweghe told reporters it had been touch and go whether she would even make it to Melbourne Park for her match.
Sock, who had squandered an early service break in the first set, went to ground early in the tiebreak, reaching immediately for his right hip.
“I grew up playing team sports. Tennis was the last sport I ever played. I‘m very used to a team atmosphere first,” CoCo Vandeweghe said ahead of the Fed Cup final.
US Open 2017: Rafael Nadal hailed by Twitterati as 'best Spanish athlete' after claiming 16th Grand Slam title
Rafael Nadal overwhelmed Kevin Anderson 6-3, 6-3, 6-4 on Sunday to win his third US Open at Flushing Meadows. Take a look at how Twitter reacted to his win.
US Open 2017: CoCo Vandeweghe credits coach Pat Cash's 'Jedi mind tricks' for calm demeanour on court
Dumped by her coach and struggling mentally, American tennis star CoCo Vandeweghe was "in shambles" three months ago before she started working with Australian coach Pat Cash.
Stanford Classic: Petra Kvitova, Coco Vandeweghe breeze through to second round in prelude to US Open
Kvitova is playing her fourth event since spending six months recovering from stab wounds to her left hand inflicted by an intruder at her home in the Czech Republic.
Novak Djokovic's enforced injury break will help him rediscover intense playing style, says Pat Cash
Twelve-times grand slam champion Novak Djokovic's enforced injury break gives him enough time to rediscover his intense playing style and will also make him mentally tougher on his return, former Wimbledon champion Pat Cash has said.
Here are the best off-beat moments from Day 4 of Wimbledon 2017
Once heralded as the future of Australian tennis, the only reputation Bernard Tomic and Nick Kyrgios have so far developed is for tanking matches.
Roger Federer slammed comments that he had engaged in "legal cheating" by taking a medical timeout at a crucial stage of his Australian Open victory over Rafael Nadal on Sunday.
Australia's tempestuous talent Nick Kyrgios has the potential to be a future grand slam champion but could just as easily be lost to the sport if he fails to get the support he needs, according to former Wimbledon champion Pat Cash.