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The Arizona Diamondbacks look to remain first in the NL West when they resume a four-game series versus the Philadelphia Phillies Saturday night from Chase Field.

Tied with defending champion San Francisco atop the division standings, the Diamondbacks can grab a series win with a victory tonight. They won the opener Thursday by a 2-1 score and posted another one-run triumph in Friday's 3-2 decision thanks to Miguel Montero's leadoff home run in the eighth.

"It feels great to help the team. I've been disappointed with myself. I know it is early, but I've had so many opportunities and just haven't gotten it done," Montero said.

Eric Chavez and Martin Prado both knocked in runs for Arizona, which prevailed for the fifth straight time and has won six of seven games. Ian Kennedy started on the mound for the D'backs and yielded two runs in seven innings, while Tony Sipp picked up the win by getting the last two outs in the eighth.

David Hernandez tossed a scoreless ninth for his first save.

Hoping to keep his current unbeaten streak on the mound intact on Saturday will be Arizona right-hander Trevor Cahill. Cahill is 2-0 with a 1.80 earned run average in his last three starts and previously toed the rubber in Monday's 9-2 pounding of the Los Angeles Dodgers.

Cahill threw seven innings of two-run ball to improve to 2-3 in seven starts and lowered his ERA to 2.80. He has made three starts in his career against the Phillies, going 1-1 with a 3.60 ERA.

Philadelphia's downward spiral continued on Friday, as the bullpen blew a 2-1 lead for youngster Tyler Cloyd. Cloyd was called up from Triple-A Lehigh Valley to take the spot of Roy Halladay (shoulder) and permitted two runs in 6 1/3 innings for a no-decision. Mike Adams was dealt the loss for allowing Montero's decisive blast in the eighth.

Cloyd was then optioned back to the IronPigs after his only appearance in the majors this season.

"They don't need a starter for a while, might as well go down there and keep pitching well," Cloyd said afterward. "Hopefully, the next opportunity they have, I can come back up and do well."

Jimmy Rollins started the game with a home run -- his 44th career leadoff homer -- and Domonic Brown stroked an RBI single for the Phillies, who have dropped three in a row and five of their last seven contests.

"We broke through, but we made some mistakes at the same time. We just didn't capitalize on our opportunities," said Phillies manager Charlie Manuel.

Cliff Lee will be tasked with trying to stop the surging Diamondbacks and halted a four-start winless drought (0-2) the last time out on Monday in a 6-2 win at San Francisco. Lee fanned six batters and did not issue a walk, while allowing two runs and five hits through eight innings.

The crafty left-hander is 3-2 in seven starts to go along with a 3.26 earned run average this season and has made five career starts against Arizona, going 3-1 with a 3.50 ERA.

The Phillies went 4-2 versus the Diamondbacks last season.