The injury came to light when Lowell had to exit Friday night's game after beating out an infield single in the 10th inning.
But he was right back in the lineup on Saturday, hitting cleanup.
Lowell is trying to find some form of treatment that works, but it's been fruitless so far.
"They're going to let me know tonight what they want to do," said Lowell. "I don't think it's any worse than it's been for the last five weeks. I told them I want to play, so I think I might get some type of injection in the next couple of days or something. I don't know. I actually just asked the trainers, and they told me they'd let me know tonight. We're going to talk to [team medical director] Dr. [Thomas] Gill."
Lowell doesn't think the injury has anything to do with the fact that he hit just .215 in July, with one homer.
"I was sore one day, and it really hasn't gone away. We've tried heat, stretch, stim, ultrasound, massage, I got a cortisone shot before the All-Star break," he said. "I don't know, we've kind of exhausted everything. It's just been a nagging thing that hasn't gone away. But it only bothers me to run, so I really can't say it's affected me swinging or affected me throwing. I'm just kind of hoping it goes away, but it really hasn't."
Manager Terry Francona appreciates the way Lowell has played through the ailment with no complaint.
"He's feeling it," Francona said. "He's been fighting this for a long time. He's a tough kid. Speed has never been a big part of what he's doing. He'll acknowledge that. But I don't want to not acknowledge that he is toughing this one out."
Lowell is likely to play again on Sunday, when the A's start a left-hander for the second day in a row. But look for the third baseman to get a night off on Monday in Kansas City against righty Gil Meche.
"I think we've tried everything, treatment-wise," said Lowell. "That's why I think we're going to talk to Doc Gill and see what he wants to do, maybe with a supersonic anti-inflammatory, [to see if] it can calm down. It's something that hinders me in one aspect of the game, but fortunately, it's not a major aspect of the game for me. I think we can live."
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.