"Scott Olsen is naturally optimistic, but even he started to worry a bit about his sprained right ankle when he hobbled off the team's charter from New York on Sunday night.

"It hurt when I got off the plane," Olsen said. "It looked bad. That's probably the worst it was."

His ankle remained tight when he got up Monday morning, but by the time he got to Dolphin Stadium it had started to loosen up. He decided to play catch in the soggy outfield grass with Matt Treanor, which led to a few minutes of long toss, and before you knew it Olsen had hopped over the bullpen fence and was climbing atop the mound.

Forty-six pitches later, including 29 from a full windup, Olsen was pronouncing himself good to go for Thursday's scheduled start against the Cardinals.

"Felt fine," he said. "I'll be out there for sure."

Olsen still can't do his normal between-starts running but will substitute time on an exercise bike or elliptical trainer instead. His ankle, injured during Saturday's start at Shea Stadium, was taped up for Monday's session, and he will continue having it taped each day.

"I never expected to miss a start; I knew I wasn't going to do that," said Olsen, who has never missed a turn because of injury in the majors. "I'm not one for missing starts. I like to be out there."

Olsen admitted his ankle probably wouldn't be 100 percent by Thursday, but as long as it doesn't affect his normal throwing motion he isn't concerned.

"I've got to pitch either way, so it's not really relevant how I feel," he said. "If it's 50 percent, I'll go out there. It's a lot better now than it was."

With Olsen on track, fellow lefty Andrew Miller (patellar tendinitis) will make a second rehab start for Class A Jupiter on Thursday. Miller should throw about 80-85 pitches."