PHOENIX (AP) -- Mark DeRosa accomplished his main goal today. Now, he's ready to return his focus to baseball.

The Cubs' second baseman played for the first time since undergoing a heart procedure on February 28th and went 0-3 in Chicago's 6-4 loss to the Milwaukee Brewers in Phoenix.

Derosa says it was great just to get out and play. He's beginning his second season with the Cubs, but he experienced a rapid heartbeat on February 23rd during infield drills. He spent a night in a hospital in Mesa before returning to Chicago for a procedure that involved using electrical energy to destroy tissues in the heart that were causing the rhythmic disturbances.

Now he's fine and focusing on getting the timing of his swing back. Dave Bush ran into early problems as he fights for one of two open rotation spots among four Brewers pitchers.

Bush gave up three runs in the first inning after he allowed four of his first five batters to reach base. But he settled into a groove quickly, retiring his final 11 in a row, including four strikeouts.

Manny Parra, also competing for a spot in the Brewer rotation, was sharp, allowing just one hit over four innings with three strikeouts. He's allowed one run this spring with a team-high eight strikeouts.

(Copyright 2008 by The Associated Press. All Rights Reserved.)