The 29-year-old arrived on Thursday morning at the club's
Melwood training complex for fitness tests which were reviewed by
Liverpool's medical team before it was decided he needed a
scan.
The England midfielder struggled with the injury during
Wednesday night's 3-1 first-leg defeat by Chelsea, when he was
man-marked by Michael Essien.
Gerrard was sidelined in February with a hamstring injury
sustained in the FA Cup trilogy with Everton, and he has also
suffered previous groin problems this term.
Before the Chelsea defeat there had been fears Gerrard was still
struggling from the ankle injury that forced his precautionary exit
from Saturday's win at Fulham. But Gerrard trained with the squad
on Monday and Tuesday, and was passed fit to play.
But now Liverpool are bracing themselves for Gerrard missing
Saturday's home Premier League game with Blackburn as well as the
quarter-final second leg at Stamford Bridge next Tuesday.
Liverpool manager Rafael Benitez was concerned about his
captain's fitness after the Blues match. He said after the game:
"Steven was not 100%, you could see that. It was the same for
Fernando Torres, you could see that they were a little tired, not
as sharp as before. "But they have been playing well and we felt it
was okay to use them both in this game. We need them.
