Hopman Cup director Paul Kilderry has a contingency plan in place should Jack Sock not recover from his hip injury in time to face Roger Federer on Thursday night.
American Sock retired early in the second set of his clash with Japan’s Yuichi Sugita on Tuesday morning, but the world No.8 is expected to be fit for their sell-out tie against Switzerland.
The winner of the tie is likely to claim Group B and win through to the final of the mixed-teams tournament in Perth.
The team of Sock and CoCo Vandeweghe are chasing the US’s seventh Hopman Cup title.
If Federer and Belinda Bencic are successful, it will be Switzerland’s third tournament championship.
After losing the opening set, Sock received treatment for an injured hip he received after he took a fall earlier in the set.
He tried to continue but retired early in the second set with the scores at 7-6(1) 1-1.
Kilderry expected Sock to bounce back but had a back-up plan, just in case.
“I just spoke to Jack and he feels like he’ll be fine,” Kilderry said.
“He has had some treatment on it and feels like he’ll be good to go. He said it felt uncomfortable out there, so I think he was just a little nervous doing more damage.
“Thursday night is a sell-out. We’ll certainly have something in place if he wasn’t to feel great, but… he’s very confident he’ll be fine. He’s had it before and he knows what he’s dealing with.”
Pat Cash, who is coaching Vandeweghe, took Sock’s place in an exhibition fast4 mixed doubles match.
Cash is not a part of the contingency plan for Thursday night, nor is the tournament’s back-up male player Blake Ellis.
Japan’s Naomi Osaka is also expected to recover in time for Japan’s next tie, against Russia, on Thursday.
Osaka did not make it to the court on Tuesday, having fallen ill on Monday night. She forfeited both the singles and the mixed doubles, automatically gifting the US both rubbers.
Osaka was replaced in her singles match against Vandeweghe by 19-year-old Perth local Maddison Inglis, who has been the hitting partner for the American this week.
Vandeweghe survived some anxious moments in the match before winning 7-5 6-2.