Reading midfielder Jem Karacan hopes he will be out for no longer than a month after damaging his knee against Liverpool.
Karacan, 23, was substituted in the 25th minute of Saturday's 1-0 defeat at Anfield when he twisted his knee in a tackle with Reds skipper Steven Gerrard.
It is another blow for the player who missed the start of the Premier League season as he battled back from a four-month lay-off with a broken ankle.
Karacan has been in impressive form since regaining his place in Brian McDermott's side and also broke into the Turkey national squad this month.
But he remains optimistic ahead of a scan this week which will assess the damage further.
He said: "I think I've opened up the medial ligaments a bit. When I did it I knew it wasn't great, but I was able to walk so I thought I could give it a go, but it was too loose.
"I'll know more this week. It's one of those things, but I've been here before. I'm hoping it won't be longer than a month.
"But I can't put any timescale on it until the scan. After breaking my ankle it's gutting - the worst runs through your mind.
"I eat, breathe and sleep football and knowing that will be taken away from me is the worst thing in the world."