Bale suffered the problem towards the end of Spurs' 2-2 draw in the first leg of their UEFA Europa League quarter-final against the Swiss side at White Hart Lane and is set to have a scan on his ankle on Friday.
His exit prompted concerns that his season could be ended prematurely but manager Andre Villas-Boas has said he is hopeful the problem is not as serious as first feared.
Bale has been Tottenham's star player this season, scoring 22 goals in all competitions, and team-mate Mousa Dembele is keeping his fingers crossed the injury will not keep the 23-year-old out for long.
"He's a player who's been unbelievably important for us this year and he can be even more important," said the Belgian.
"We all hope that he will be fit."
Gylfi Sigurdsson, who scored the equaliser for Spurs after Emmanuel Adebayor had pulled them back into it from 2-0 down, admits it is a case of waiting to see how serious Bale's injury is.
Aaron Lennon was also injured early on in the clash and Sigurdsson, who replaced the winger in just the 24th minute, feels his absence could also prove an untimely blow.
"Hopefully (Bale) will recover quickly and recover for the next few matches," he added.
"Lennon obviously came off as well and he's very important to us. They're top quality players and hopefully they'll get back soon."
Goalkeeper Brad Friedel, who took over from Hugo Lloris between the sticks on Thursday night, agrees it is a waiting game for Spurs over Bale.
He added: "We'll have to wait and see. Nobody at this moment in time knows how severe it is."