Delmon Young's journey to become the Phillies' starting right fielder took another step Sunday when he donned a Clearwater Threshers uniform. His official minor-league rehab assignment started, and if the initial results are any indication, improvement is required.

The first Lakeland Flying Tigers batter hit a fly ball at Young and it landed for a triple. Young should have limited the hitter to a single had he taken a better route, said two officials who attended the game in Lakeland, Fla. Later, in the seventh inning, Young committed a fielding error that allowed a runner to take an extra base.

He batted cleanup in single-A Clearwater's lineup and went 1 for 4 with a sacrifice fly and single. While the Phillies are evaluating Young's bat, they are primarily concerned with his defense.

"Obviously we want his bat, but if he can't play defense he can't play in the National League," Phillies general manager Ruben Amaro Jr. said. "He's going to have to be adequate out there. Until today he hadn't screwed up any balls, but today he did. ... He's got to play adequate defense out there for us in right."

Seven balls were hit Young's way and he misplayed those two. A scout who watched Young on Sunday said the outfielder moved better and without hesitation. Young spent the majority of 2012 as a designated hitter for Detroit. He last played right field in 2007. The Phillies want him there.

Barring a setback, the latest possible date Young can make his Phillies debut is May 11. Official rehab assignments can last 20 days in the minors. Young is recovering from microfracture surgery on his ankle done last November.

Manager Charlie Manuel said Young will probably spend "a couple of weeks" in the minors.

"If he can produce some offense, we can [substitute] for him in the outfield late in the game," Manuel said. "It's not like we want to embarrass him. But if he can help us offensively, then that part will stand out. More than likely, we'll give him a chance."

If the Phillies activate Young, he will instantly receive a $225,000 bonus. He is guaranteed a $750,000 base salary. The total value of the deal, including bonuses, is $3.5 million.

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