Seahawks coach Pete Carroll said it's likely that Hasselbeck, scheduled to undergo an MRI exam Monday, won't practice this coming week. Seattle plays St. Louis Rams next Sunday for the NFC West title.
"We'll watch closely what happened with Matt," Carroll said. "We'll have to see how that works out. We'll give him all week. Just rest him and see what happens."
Hasselbeck was hurt on a 1-yard touchdown run in which he rolled out of the pocket to his right and ran into the end zone untouched with 2:50 remaining in the opening quarter. He bent over for a moment, started to walk off the field and then stopped again before sitting down in the end zone.
"It just got real tight on me real fast," said Hasselbeck of two muscles in the hip. "That was disappointing. I tried to come around real quick and it's just how I hurt it."
Hasselbeck eventually walked to the sideline under his own power. However, Charlie Whitehurst replaced him on Seattle's next possession, with the Seahawks leading 7-3. Tampa Bay wound up winning 38-15.
"As of right now, we're getting Charlie ready to go," Carroll said.
Whitehurst completed 11 of 18 passes Sunday for 66 yards.
"I'm preparing like I'm playing the game," Whitehurst said of the showdown with St. Louis. "If that changes, I'll take it as it rolls."