WASHINGTON -- Mike O'Connor had a lot of friends and family rooting him on.
"It felt a little weird knowing everybody was watching me," he said. "I just tried to focus on the game and making pitches and tried not to worry about that."
O'Connor won for the second time in three starts since joining the Nationals' rotation, getting a two-run homer from Jose Guillen in the Washington Nationals' 5-4 win over the Pittsburgh Pirates on Sunday.
A 2002 graduate of George Washington University with a degree in finance, O'Connor (2-1) allowed three runs, five hits and four walks in five innings, hitting two batters and throwing a wild pitch. He lost 6-2 at St. Louis in his major league debut on April 27, then won 6-2 at the New York Mets on May 2.
O'Connor said he got about 20 tickets for family and friends and that his parents purchased about another 100. His coach from Mount St. Joseph High School also brought his team from Baltimore.
"I knew there were a lot of people here to see me," O'Connor said. "I didn't really talk to anybody today, but it's definitely a different feeling knowing there's a lot of people here. I saw a lot of people while I was warming up. When I was walking out there, a lot of people were yelling at me that I've known.
O'Connor walked Jose Bautista to open the game and hit Nate McLouth, his second batter. After allowing a run-scoring double by Jason Bay and walking Craig Wilson, he got out of a bases-loaded jam by striking out Ronny Paulino.
"It was definitely a little shaky early, but I was able to get through some innings without giving up too much," O'Connor said. "I was able to make pitches when I needed to. It was definitely good to get out of that with just giving up one run early."
Pittsburgh stranded six runners in the first three innings and 11 overall.
"The kid has a lot of heart," Nationals manager Frank Robinson said. "He doesn't back down and doesn't back off. He seems to get a little tougher when things get a little tough. I saw some of that in the first two games he started and I really saw it today in the first inning."
Washington took a 5-1 lead in the third when Nick Johnson hit a two-run single, Guillen followed with his third homer, and Ryan Zimmerman and Matthew LeCroy hit consecutive doubles that gave the Nationals four straight hits.
"Nick gets jammed and bloops one in there, and we score a couple," Robinson said. "It looked like it loosened everybody up, and they got some pitches to hit. Guillen's was a big, big hit. It was good to get out in front and give our staff a cushion to work with."
Guillen's home run was his first at RFK Stadium in 33 games and 108 at-bats since last Aug. 24 against Cincinnati's Ramon Ortiz.
"I keep telling everybody: 'Don't worry about me, I'll be all right,"' Guillen said. "I'm struggling, but I will find my way to dig out of this slump."
Relievers Jason Bergmann, Felix Rodriguez, Mike Stanton and Chad Cordero finished for the Nationals, with Cordero getting four outs for his third save, his first since April 16 at Florida. Pittsburgh had three hits off the bullpen, all against Stanton.
The Nationals won two of three from the Pirates for their first series win since taking two of three at Philadelphia from April 18-20.
"I'm relieved to win a series anywhere," Robinson said. "We could have been in the Mojave Desert today and I would've been relieved."
Zach Duke (2-3) gave up five runs and eight hits in six innings for the Pirates, who dropped to 3-17 on the road this season.
"The great pitchers, they don't allow the big innings," Duke said. "That's what I allowed today. That's unacceptable on my part. I let it get out of control."
Pittsburgh has lost six of eight overall.
"Today boils down to missed opportunities offensively," Pirates manager Jim Tracy said. "We had a tremendous opportunity in the first inning and we pop up and fly out to end the inning. We had first and third in the third inning, and we pop up and flied out."
Pittsburgh's Freddy Sanchez capped a 13-pitch at-bat in the fourth with a two-run triple down the left-field line.
"I didn't have two many quick innings," O'Connor said. "Every inning was pretty much a battle for the most part. It was nice to get through it with only giving up the three runs."
Jose Bautista had an RBI single in the eighth off Stanton, and Cordero relieved with runners at the corners and got Sanchez to hit into an inning-ending forceout.
Marlon Byrd's third-inning single was his first hit in 18 at-bats this season at RFK Stadium. He is hitting .348 (16-for-46) in 17 road games. ... Zimmerman doubled twice. ... The Pirates fell to 1-12 in games started by LHP. ... Sanchez had to hustle back to the batter's box in the fourth inning after running to first base when he thought he drew a walk with only three balls.