Andy Wilkinson could miss Stoke's final four games of the season after being sent for a scan on his hamstring injury.
The full-back limped out of the Potters' 3-0 defeat at Newcastle with the problem and is now undergoing tests to ascertain the full extent of the damage.
Pulis is waiting on the results and has urged caution on whether he will feature in the run-in to the season, especially as Wilkinson only just returned from a two-game absence when playing at the weekend.
"He actually feels better now than when he came off on Saturday," Pulis said. "But it's still bad enough to send him for a scan on the hamstring, which will happen today.
"We'll obviously wait to see what the results bring before deciding how to go with Andy, but time is clearly running out this season."
Meanwhile, Pulis has also given an update on Jermaine Pennant's fitness as he recovers from a virus.
The winger was hoping to be available to face his former club Arsenal this weekend but it remains touch and go if he will make it.
"He has been training all right so far this week, but he's still not as sharp as he can be," added Pulis in the Sentinel. "When you've had a virus like he's had, it does take it out of you."