Mets-Diamondbacks Preview

When the Arizona Diamondbacks acquired Jason Marquis at the trade deadline, they hoped the veteran could bolster the back end of the rotation for a playoff run.

He's done nothing to help that cause even though their postseason hopes have gotten much better since his arrival.

Marquis looks to bounce back from another discouraging outing and help the Diamondbacks extend their winning streak to six games in Sunday's series finale against the slumping New York Mets.

Arizona acquired Marquis (8-6, 4.48 ERA) from Washington on July 30, after the right-hander recorded a 3.95 ERA in 20 starts for the Nationals. Marquis has a terrific track record of pitching for playoff teams in 10 of his first 11 seasons, and the Diamondbacks (67-53) were hoping for a similar end result.

They were four games behind San Francisco for the NL West lead when they traded for Marquis but have since moved into first place, two games ahead of the Giants. Arizona, which finished last in the West each of the last two seasons, is seeking its first playoff berth since 2007.

"We're in a good spot," manager Kirk Gibson said after Saturday's 6-4 win over the Mets. "It's going to get much, much, much tougher, physically and mentally. But we try to keep our team in a position where we'll be able to withstand it."

Gibson now needs Marquis to show some fortitude after a couple of forgettable outings since joining the Diamondbacks.

After being tagged for a season-high eight runs and 10 hits in four-plus innings in an 8-1 loss to the Giants on Aug. 3, he yielded seven runs - four earned - and nine hits in four innings of an 11-9 comeback win over Houston on Tuesday.

"I have to do a better job of putting batters away when I'm in control of the count," he said. "I'm not trying to put too much pressure on myself. I just want to go out there and pitch the way I have all year."

Marquis had a solid outing in his lone start of the year against the Mets on April 10, giving up three runs and striking out nine in six innings of a 7-3, 11-inning win for Washington.

Arizona has won five straight home games over the Mets, and five in a row overall. Ryan Roberts hit a go-ahead three-run homer in the fifth inning Saturday, and Justin Upton notched his team-leading 74th RBI.

The Mets (58-61) have lost four straight and 10 of 13 to fall three games below .500 for the first time since June 21. They haven't been four games under the break-even mark since June 4, when they were 27-31.

Saturday's defeat was somewhat overshadowed by a story that ran in The New York Post earlier in the day that quoted Mike Pelfrey as saying anyone who expected the Mets to win it all this season was being "unrealistic."

"I said something that was misinterpreted," said Pelfrey, Saturday's losing pitcher.

David Wright and Jason Bay were each 0 for 4 on Saturday but could have better luck in the finale. Wright is hitting .406 lifetime against Marquis, while Bay is batting .372 with five homers and four doubles in 43 at-bats against him.

The Mets counter with Chris Capuano (9-10, 4.51), who has yielded at least four runs in four of five starts since the All-Star break. He gave up four runs and nine hits in six innings of Tuesday's 5-4 win over San Diego, but didn't receive a decision.

Capuano is 1-3 with a 3.77 ERA in six games versus the Diamondbacks but hasn't started against them since 2007.