BRADENTON, Fla. — Chris Duffy needed only a few weeks in the majors last season to convince the Pittsburgh Pirates that he can be the reliable and offense-creating center fielder they have sought since the Andy Van Slyke days in the early 1990s.

Excellent defensively, Duffy showed flashes of being a disruptive player on offense who can get on base, run the bases and generate runs while hitting .341 — with an on-base percentage of .385 — in 39 games following his July 17 call-up.

Now the challenge for the Pirates is to keep Duffy on the field and off the disabled list.

Duffy returned from an eight-day layoff with a mild concussion to go 1-for-4 with a double and three strikeouts in a 9-7 exhibition game victory against the Toronto Blue Jays on Sunday.

Duffy's injury, which resulted from being hit in the helmet by a Curt Schilling pitch on March 11, followed a rotator cuff problem earlier in camp and a torn hamstring that sidelined him from Aug. 25 on last year — a premature finish to a promising debut season.

"I had a little bit of trouble picking up off-speed pitches, but that is going to come," Duffy said of returning to the lineup. "I'm not where I need to be by any means, but that will come."

The Pirates don't necessarily think Duffy is injury-prone. But he is relatively old as far as prospects go — he turns 26 next month — and he can't afford to take off a lot of time.

Especially not on a team that, despite losing 95 games last season, is deep enough that it expects to open the season with Craig Wilson, who hit 29 homers in 2004, and Jody Gerut, who had 22 homers for the Indians in 2003, as spare outfielders.

"We need to speed him up with his at-bats," manager Jim Tracy said. "He needs to catch up a little bit. But we can get him to 45 or 50 at-bats very easily."

Duffy is not having a great spring, hitting .227 in 22 at-bats, but he still expects to be the starting center fielder April 3 in Milwaukee. He knows he has to produce, especially since he is being pushed for playing time by Nate McLouth, who also debuted with Pittsburgh last season.

McLouth, 23, is having a better spring than Duffy with a .364 average.