"The big thing that struck me last night was locating those pitches, and I think he would probably say the same thing," Mills said. "When the catcher is setting up away and the pitch winds up over [the plate], something's different. That's not him."
Lyon missed 32 games with right biceps tendinitis and a partial rotator cuff tear and returned to action Friday and gave up a home run in one inning.
"Maybe he's getting a feel for it," Mills said. "We're going to have to do what we can to find out why Brandon Lyon isn't throwing the ball like Brandon Lyon can."