Matt Harrison's start Thursday in doubt

ARLINGTON, Texas -- Matt Harrison said Tuesday that he felt some improvement in his sore lower back, but he didn't throw his usual bullpen session, leaving Thursday's scheduled start in Seattle in doubt.

The Rangers have already discussed some options if Harrison can't go. General manager Jon Daniels said the team is better off being cautious at this point in the season. Harrison was able to play catch Tuesday.

"If this was September, he would make his start," Daniels said.

Harrison said the weakness is his back area goes down to his left leg. That's his push-off leg, which could explain why his sinker was up in Saturday's start against the Angels when he allowed two first-inning home runs. Harrison has been dealing with back soreness for two weeks.

"It may be better to nip it in the bud now," Harrison said. "I'm optimistic. I want to be out there every five days."