PITTSBURGH - Jeff Karstens picked up where Ross Ohlendorf left off.

Pittsburgh's pitchers are feeding off each other's success these days.

Karstens pitched six sharp innings, Freddy Sanchez homered and the surging Pirates beat the Florida Marlins 3-2 Tuesday night.

Karstens allowed one run and three hits for the Pirates, who lead the league in ERA and have won four of their last five games. Sanchez finished with three hits.

"A lot of people doubted us, but we all believe in ourselves and we all believe in each other," Karstens said of the staff that has a 3.00 ERA so far this season after finishing with an NL-worst 5.10 ERA last year. "That's all that matters right now. Enough can't be said for (new pitching coach Joe Kerrigan); we're more prepared than any team in the league."

Ohlendorf allowed two hits over seven innings as Pittsburgh beat Florida 8-0 Monday for its third shutout in four games. The Pirates have four shutouts this season; the other 13 NL teams have combined for six. Pirates starters have allowed more than two runs in four of their 14 games.

"Those guys are giving us a chance to win ballgames," shortstop Jack Wilson said.

Cameron Maybin hit his first National League homer for Florida, which has lost two straight against the Pirates after opening the season with an 11-1 stretch.

Matt Capps pitched the ninth for his fourth save.

Karstens (1-0) won for the first time since Aug. 6, when he took a no-hitter into the eighth inning at Arizona. Karstens, acquired from the New York Yankees in the Xavier Nady trade in July, didn't allow a run in his first two Pirates starts but had been 0-6 since.

"He kept the ball down and did a nice job," Pittsburgh manager John Russell said. "He got through six, which is pretty solid start for him at this point of the season."

The Pirates scored in each of the first three innings to build a 3-1 lead. Adam LaRoche drove in Nyjer Morgan with a first-inning single, and Jason Jaramillo picked up his first major league RBI with a run-scoring double in the second.

Sanchez led off the third with a drive to left-center off Anibal Sanchez (1-1). The 2006 batting champion is hitting .476 (10-for-21) over his last five games.

Maybin got Florida within one with a leadoff shot in the eighth that traveled an estimated 447 feet. The Marlins put two runners on later in the inning but John Grabow retired Hanley Ramirez on a popup and struck out Ross Gload to end the threat.

Notes: Pittsburgh's Andy LaRoche has eight hits in his past 19 at-bats after beginning the season in a 0-for-18 slump.