Kenzie Fowler, who threw Tuesday for the first time since leaving Saturday's game in pain, said she anticipates being ready when the Arizona Wildcats host Washington starting Friday.
The sophomore left Game 1 of Saturday's doubleheader at Oregon State after 1 1/3 innings with pain in her left hamstring after landing awkwardly in the pitcher's circle.
Fowler had been dealing with tendinitis - swelling near where the hamstring reaches her knee - since the UA hosted Baylor on March 12-13.
"Just taking precaution on it," Fowler said. "I've been dealing with this the last four weeks."
Fowler, who wore a black sleeve over her left knee Tuesday, has been taking anti-inflammatories and using stretching, ultrasound treatments and ice on the injury.
Trainer Emily Anaya said there was no reason to think the injury could get worse.
A lower-body injury is problematic for pitchers.
"It's where your strength lies," UA coach Mike Candrea said. "It's a kinetic link. … It works from the bottom up."
The Wildcats (34-7, 5-1) and weekend foe Washington (29-4, 4-2) are ranked seventh and eighth in the ESPN.com/USA Softball Collegiate Top 25, released Tuesday, and are flip-flopped in the USA Today/NFCA Div. I poll.
At 37-4 (4-2), ASU moved into first place in both polls, a move Candrea said he was fine with despite not leading the Pac-10.
For the Wildcats to pass them in the polls this year, they'll need Fowler. Asked how important Fowler was to the season, left fielder Brittany Lastrapes paused.
"I don't really think I can put it into words," she said. "It's definitely scary. She's essential to our success."
• What: Washington at Arizona, three-game series
• Where: Hillenbrand Stadium
• When: 7 p.m. Friday; 7 p.m. Saturday; noon Sunday