Grabow says he's ready to go

Pitcher John Grabow threw in the outfield Monday with Cubs trainer Mark O'Neal and proclaimed himself ready to pitch.

Grabow missed the final two games over the weekend in Cincinnati with a sore left knee. He returned to Chicago for an MRI, which the Cubs said showed no structural damage.

Manager Lou Piniella, however, said Grabow had a cortisone shot.

"It's something I've been pitching through for a while," Grabow said. "It's been bothering me for a few weeks now. I tried to pitch through it. I thought maybe it would go away. It hadn't gone away."

Grabow got off to a rough start, with a record of 0-2, an ERA of 9.26 and a high WHIP of 2.14 entering Monday.

"I think it's changed my mechanics a little bit," he said of the knee. "I don't know if it's so much change the way I pitched or not as far as results. It's something I wanted to try and nip in the bud."

Eighth for now: Rookie shortstop Starlin Castro batted eighth in Monday's lineup. Eventually, the Cubs may see him as more of a top-of-the-order hitter.

"I think so," said Lou Piniella. "You might see him later on this summer if he continues to swing the bat well. We're just staring him out in the 8-hole just so he gets some at-bats and sees some major-league pitching, and see how he responds. It doesn't mean he has to stay there the rest of this year. We'll see how he's doing, and we'll react accordingly."

Minor matters: The Cubs recently promoted right-hander Andrew Cashner from Class AA Tennessee to Class AAA Iowa. The Cubs plan to keep him a starter for the time being, thinking he needs innings more than anything else.

"He was throwing well; he was on a roll," said farm director Oneri Fleita. "Start after start, 6-7 innings. He earned it. He did a good job. You love to get guys on a roll like that and put them at the next level. You want to see guys dominate a level, and he was doing that. This will be new challenge for him now at Triple-A."