On Tuesday, he pulled the trigger. Piniella removed Gregg as the closer and replaced him with right-hander Carlos Marmol, who has been the team's ace setup man since 2007.
Gregg is 23-for-29 in saves, and his .793 save percentage ranked 14th in the National League entering Tuesday.
Marmol is not without his problems, though. He has electric stuff -- as evidenced by allowing only 31 hits in 56 1/3 innings -- but has walked 52 and hit 11 batters.
"Obviously, he has the stuff to do it, and he has the toughness to do it," Piniella said. "It's just a question of getting the ball over the plate."
Gregg beat out Marmol for the job in spring training after Marmol had a tough time pitching for the Dominican Republic in the World Baseball Classic, during which he struggled with his command. Marmol was hurt at the time, but he said he "believed" in himself. Marmol saved seven games last year, helping out when erstwhile closer Kerry Wood was on the disabled list.
Gregg is headed for an unspecified setup role. Lefty John Grabow and righty Angel Guzman appear likely to share eighth-inning duties in close games.
PADRES 6, CUBS 3: RHP Ryan Dempster fell to 6-7 by giving up eight hits and four runs in seven innings. First baseman Derrek Lee hit his 24th home run of the season in the first to give the Cubs a short-lived lead. RHP Angel Guzman gave up an inside-the-park two-run homer to Kyle Blanks in the eighth. The Cubs are 0-5 in San Diego this year.
--LF Alfonso Soriano picked up the 1,500th hit of his career when he dropped an RBI single into left field in the fifth inning Tuesday. Soriano has not homered since July 29.
--2B Jeff Baker extended his hitting streak to eight games when he singled in the second inning Tuesday. Baker, who doubled in the fourth, is 16-for-32 during the streak. Piniella says Baker figures to get most of the playing time at second ahead of Mike Fontenot, who has endured a disappointing season.
--Dempster tied his season-high with 121 pitches over seven innings in Tuesday's loss to San Diego. Dempster, a 17-game winner last year, fell to 6-7. He reached double digits in strikeouts, with 10.
--SS Ryan Theriot rejoined the team after missing two games with a bad stomach virus. Theriot moved back into the leadoff spot and went 0-for-5.
--Guzman's first test as an eighth-inning setup man did not go well. He walked Will Venable leading off before giving up an inside-the-park homer to Blanks, who beat the Cubs with a conventional homer the night before. Guzman walked another batter before getting out of the inning without further trouble.
Piniella Makes Change at Closer
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