PHILADELPHIA—It wasn’t just one botched ball.

Delmon Young, making his first minor league rehab assignment start yesterday in Class-A Clearwater, booted one in the seventh inning to let a runner take an extra bag.

But more troubling, maybe, was that the 27-year-old right fielding hopeful poorly misplayed the first ball put in play, an eventual triple for the Lakeland Flying Tigers that scouts there said would’ve been only a single had Young taken a better route on it.

In all, Young had seven chances yesterday, the first step in his preparation for and the team’s evaluation of his play right field for the first time since 2007. He whiffed on two.

It’s early. But it’s not the no-news-is-good-news fielding report the Phillies hope to hear.

"Obviously we want his bat, but if he can't play defense he can’t play in the National League," GM Ruben Amaro Jr. said yesterday.

"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."

Per league rules, the latest Young can get the big league call is May 11. Official rehab assignments can last no longer than 20 days, though that will reset if there’s a setback.

A job may be awaiting him. It may be the job Amaro said he'd hoped it to be when he signed him this winter. It may be on the bench.

John Mayberry was penned in the two-hole in Charlie Manuel’s lineup for the second straight day Monday for the series opener with the Pittsburgh Pirates. His manager seems to like him there, and in right field, maybe enough to block Young.

"When you play good you always have a chance," Manuel said. "

He’s hitting .300, isn’t he? A .400 on-base percentage. About 38-40 at-bats. ... He’s got six walks. You guys are talking about how we don’t get no walks. He’s got six of them."

Mayberry's .316/.409/.553 line in 17 games this year makes for a sweep of team-highs. League-wide, two-hole has increasingly become an extension of the three-hole, which is reserved for a team's best hitter. (Or, in this case, best performer for the moment.)

Mayberry also flashed the requisite speed to get from second to home and first to third on singles, and even swipe a bag, as he did last night against the Cardinals for his first of the year.

Mayberry's ups and downs are well-known, and so while his 7 for 19  (.368) run in his last seven games it can't be taken without pause.

Charlie Manuel knows this, and yet didn't hesitate to again reiterate the possibility that Mayberry's play commands an everyday spot in right field -- relegating Young to being the bench player Mayberry once was, and may be playing his way out of.