Wasps have sent England internationals Elliot Daly and Nathan Hughes for specialist evaluation after both suffered injuries in Sunday's European Champions Cup win over La Rochelle.
Daly scored a brace of tries in a 21-3 over the Pool 1 leaders at the Ricoh Arena, but was forced off in the second half with an ankle issue.
Hughes suffered a knee injury, as did fly-half Jimmy Gopperth, with Wasps director of Rugby Dai Young revealing both had picked up MCL injuries.
Young remains hopeful that Daly has not sustained a serious injury, easing fears from England fans with the Six Nations less than two months away.
"They are all seeing specialists tomorrow [Wednesday], so we'll know more then, but we can certainly say they'll be out for a few weeks," Young told reporters.
"Elliot has injured his ankle - he has a syndesmosis injury - which is pretty common.
"He is going to see the specialist to see whether any surgical intervention is required, which depending on the grade of the injury hopefully it won't be."
Hughes played in all of England's 2017 Six Nations fixtures, as well as the November Internationals against Argentina and Australia.
His participation in the 2018 Six Nations looks less clear.
"Jimmy and Nathan both have MCL injuries to their knees," Young explained.
"Again, we're waiting on the specialist to let us know what is required, but we can safely say even the best picture, which is a grade one tear, will require a minimum of four weeks."