Another strong performance from the veteran knuckleballer could prevent New York from falling even further back in the standings.Dickey tries for a 12th consecutive winning decision and Gonzalez looks to rebound from his ugliest outing of the year Tuesday night as the slumping Mets continue a three-game set with the NL East-leading Washington Nationals, who won't have Ian Desmond available after placing him on the disabled list.While Dickey (13-1, 2.84 ERA) has cooled off quite a bit since going 9-0 with a 1.21 ERA over an 11-start stretch April 25-June 18, he came up big during Thursday's 9-5 win at Nationals Park. The right-hander allowed 10 hits but was able to limit the damage, yielding three earned runs over 7 1/3 innings to improve to 2-0 despite a 4.86 ERA over his last five starts."I haven't pitched as well as I have in that streak. That's hard to expect," said Dickey, who also allowed a two-run homer during an inning of relief in Saturday's 8-5 loss to the Los Angeles Dodgers."You have to have a lot of cooperation. Recently, I've just been so-so. Hopefully, I get a second wind here."The Mets (47-49) may feel like they're facing a head wind. New York has compiled a 6.41 ERA while dropping 10 of 11 -- including a 1-9 record since the Midsummer Classic.The Mets were handed their seventh loss in their last nine meetings with Washington on Monday, falling 8-2 in 10 innings. After hitting a two-run homer in the first inning, Bryce Harper singled home the go-ahead run in the 10th before Ryan Zimmerman broke the game open with a three-run double. Michael Morse followed that with a two-run home run.Winners of three in a row overall and seven of eight at Citi Field, the Nationals (56-39) now sit 9 1/2 games ahead of the third-place Mets."Coming to New York, all the fans love their teams, you just try to come in here and play it like another team," Harper said.Though they've been playing well, the Nationals know overcoming Desmond's absence won't be easy. The All-Star shortstop, who leads the team with 17 homers, tried to play through an oblique injury but was placed on the 15-day DL on Monday after an MRI showed a tear on his left side."He's been our MVP all year," utility man Mark DeRosa told the team's official website. "Big hit after big hit. He's basically been the captain of our infield for all of the first half of the season. So to lose him is tough."The Nationals now turn to Gonzalez (12-5, 3.32), who's been a bit shaky lately. The left-hander went 7-1 with a 2.04 ERA over his first 10 starts but has since posted a 5-4 record with a 4.93 mark in nine outings.Gonzalez struggled mightily opposite Dickey on Thursday, surrendering a season-high six runs along with six hits and three walks over 3 1/3 innings in his shortest appearance of the year."Just felt a little flat," Gonzalez said. "Nothing was moving too much. They did a great job attacking me right off the bat. They were swinging aggressively and going after me right off the bat. Make better pitches, get better outs."You gotta learn you're gonna hit some patches once in a while."Dickey has more than held his own in this series since the start of 2010, going 4-3 with a 2.80 ERA over 10 starts. Danny Espinosa is 1 for 17 in their matchups while Harper's gone 0 for 7.