Steven Gerrard will undergo a scan on Thursday to discover the seriousness of the injury which threatens to cause a rift between Liverpool and England manager Fabio Capello.
Gerrard limped out of England's 2-1 defeat against France at Wembley with a hamstring problem after 84 minutes, even though Liverpool had wanted him to play for an hour only.
It prompted Darren Burgess, Liverpool's head of fitness and conditioning, to vent his anger on Twitter immediately after the final whistle.
Burgess said, in a post that was later deleted from his page: "Unbelievable from all associated with England and English FA with regard to Steven Gerrard's injury. Completely ignored agreement and past history."
The Liverpool captain could now be sidelined for weeks but Capello insisted he had no choice but to stick with him because Manchester City midfielder Gareth Barry had an ankle problem.
Capello said: "We spoke with Steve and he said he would play one hour, but after Barry's injury we had some problems. That was the reason he stayed on the pitch. If it's possible, the players will play the time we agreed with the club.
"But Barry was really injured so we needed someone senior on the pitch because it was a really young team. He said he was good. We're upset about what happened to Steve, of course."
Capello admitted Liverpool had requested that Gerrard should not play more than an hour.
He said: "They asked that he can play one hour if it's possible. They can't decide how long a player plays with the national team. If it's possible, he'd have played an hour. I understand why they're upset and I'm also upset.
"The problem is that, when you play this game on Wednesday after a lot of Premier League, Europa League or Champions League games, it's possible there might be an injury for a player. The Premier League, every time, is a tough league for the players."
Karim Benzema and Mathieu Valbuena scored the goals for France while substitute Peter Crouch grabbed a late consolation for England, the 22nd of his international career, when he volleyed home a corner from close range.
Copyright (c) PA Sport 2009, All Rights Reserved.