Zambrano likely to make rehab start this weekend

CHICAGO (AP) -- Cubs ace Carlos Zambrano will likely test his strained left hamstring in a rehab start this weekend, and is on track to return from the disabled list on May 22.

Cubs manager Lou Piniella said Tuesday before Chicago played the San Diego Padres that Zambrano will have a bullpen session Wednesday and work on running Thursday before deciding if he makes the start in Clearwater, Fla.

Piniella said the Cubs are "pretty sure" Zambrano will pass those tests.

Zambrano (3-1, 4.50 ERA) went on the 15-day disabled list on May 4, a day after injuring himself trying to beat out a bunt.

Randy Wells will make his second start on Friday and Sean Marshall will throw Saturday. Piniella said one of those two will probably go to the bullpen when Zambrano returns.

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