• Quality debut: Although he didn't get the win, Joel Hanrahan surrendered three runs and struck out seven in his big league debut Saturday.
• Good form: The Nationals have won eight of their last 13 games.
• Fantasy alert: Chad Cordero saved his 21st game of the season.
• Quotable: "It's just one hit but it gives me confidence." -- Langerhans
-- ESPN.com news services
Nationals 6, Mets 5
Langerhans singled in the go-ahead run in the eighth inning and the Washington Nationals beat the Mets 6-5 Saturday night for a split of their day-night doubleheader.
"It's just one hit but it gives me confidence," said Langerhans, who was stuck in a 0-for-16 rut before the single. "It's been a while since I had a hit to the opposite field. I'll take it and run with it."
Joel Hanrahan pitched six innings in his major league debut and tripled in his first at-bat for the last-place Nationals, who have won three of four. Washington would win the four-game series against NL East-leading New York with a victory on Sunday.
In the first game, Hernandez threw seven crisp innings in the Mets' 3-1 win.
New York finished the day without two All-Stars. Center fielder Carlos Beltran didn't play in either game because of a stomach muscle strain, and catcher Paul Lo Duca left the nightcap with an injured right hamstring.
"I've pulled this hamstring now over my career, gosh, I don't know how many times," he said. "It's the same one, same nagging thing. It's not as severe as I've done it before so I feel like I'll be all right."
Lo Duca said he was going to get an MRI exam and insisted he would catch Tuesday night in Milwaukee when Tom Glavine goes for his 300th career win. The Mets, who optioned Mike Pelfrey back to Triple-A New Orleans after the second game, could call up a catcher Sunday if Lo Duca can't play.
Carlos Delgado hit a two-run homer in the Mets' three-run sixth inning in the second game, but the Nationals went ahead for good in the eighth.
Hernandez cruised through the punchless Nationals, who were last in the majors in runs, homers and RBIs entering the opener. He struck out eight, walked two and allowed just three hits.
"When I have my curveball, my slider, it's very good," he said, "and my control was very good for me."
Ruben Gotay's RBI single in the seventh inning gave the Mets a 2-1 lead and made a winner out of Hernandez (7-4), who has won three straight decisions. New York has won 11 of El Duque's 17 starts this season.
"Not many guys can do what he does, throwing his breaking ball for strikes as consistently as he does," Mets manager Willie Randolph said. "He never surprises me."
Aaron Heilman worked a perfect eighth for the Mets, and Billy Wagner got three outs to finish off the three-hitter and earn his 24th save. It also was save No. 348, moving him past Randy Myers for seventh on the career list.
"I felt pretty good but it was a tough pitching matchup against El Duque," Redding said. "He's been pitching really well lately, especially at home."
Hernandez retired his last five batters and threw 62 of 99 pitches for strikes. He is 3-0 with a 1.13 ERA in his last six starts at Shea Stadium.
"He's got about 10 pitches from four different arm angles," Nationals manager Manny Acta said. "You know we just couldn't do anything with him."
Lastings Milledge started both games in center field with Beltran out. He hasn't played since Tuesday and Randolph said he isn't sure when he'll be able to return.
Lo Duca grabbed his right leg rounding second in the seventh inning of the nightcap. Randolph, third base coach Sandy Alomar Sr., and a trainer all came out to check on Lo Duca, who tried to walk it off before deciding to depart.
Hanrahan tripled and scored in Washington's three-run third. He gave up three runs and four hits, struck out seven and walked one.
"He showed out there that if he can command that fastball, that changeup and that breaking ball that he has he can be successful up here," Acta said.
Pelfrey also went six innings for the Mets, and was charged with eight hits and three runs. The right-hander walked one and struck out five in his first start since July 6. He remained winless in seven decisions this season.
"I've just got to continue to worry about executing pitches and just eliminate some mistakes," he said. "Definitely just have to keep working."
The Nationals finalized a $10 million, two-year contract extension with Dmitri Young through 2009. ... New York optioned INF Anderson Hernandez to Triple-A New Orleans after the first game and recalled Pelfrey. ... Hanrahan took the roster spot of RHP Jason Bergmann, who was placed on the 15-day DL Friday with left hamstring tightness. ... The day-night doubleheader was the second at Shea Stadium. The Mets and Los Angeles Dodgers played one on May 11, 1972. ... Glavine pinch hit in the ninth inning of the second game, becoming the first Mets pitcher to do it since Glavine did it on Sept. 11, 2004, against Philadelphia. He grounded out against the Nationals.