AP Sports Writer
WASHINGTON (AP) -- Every game the Chicago White Sox have played so far this season was tight.
Five were decided by one run. None by more than three, including Chicago's 5-2 loss to the Washington Nationals on Wednesday night.
One statistic that stood out from that latest close call: Chicago went 0 for 5 with runners in scoring position.
"We've had opportunities in a lot of games to jump out to either an early lead or tie some games up or blow a game open," cleanup hitter Adam Dunn said, "but it's the big hits that we're really just not getting right now."
Back in the lineup and playing left field after a day off with no designated hitter for an interleague series in an NL ballpark, Dunn came up with two men on in the first inning and drove home a run off Jordan Zimmermann (2-0) with an RBI groundout.
But the only other run Chicago pushed home Wednesday was with another run-scoring groundout, by No. 3 hitter Alex Rios in the sixth inning.
It was a game delayed 16 minutes at the start because, the Nationals explained, the umpires got caught in a traffic jam.
"I've been stuck in traffic many a time here in D.C. I'm surprised they got here as fast as they did," Nationals shortstop Ian Desmond said with a smile. "It's always an adventure here."
Desmond had a triple and a pair of doubles, Bryce Harper homered, and Danny Espinosa provided his first two RBIs of the season, helping the Nationals improve to 5-0 at home. Zimmermann limited Chicago to two runs and seven hits in seven innings.
"We threw a lot of fastballs inside," said Zimmermann, who is 7-0 with a 2.91 ERA in his last 13 home starts, "and got a lot of broken bats."
Johnson said the umpires "called in about 40 minutes before the game and said that they were a mile away, but it may take forever."
He added: "Didn't seem to bother Zim too much. Pitched a great ballgame."
Drew Storen pitched the eighth, and closer Rafael Soriano worked around a hit in the ninth for his fourth save in five chances.
Harper hit his fourth homer into the second deck leading off the fourth against Gavin Floyd (0-2), who allowed five runs and nine hits in 5 1-3 innings. Harper turned on Floyd's first pitch of the at-bat, an 86 mph offering that never stood a chance. With a "thwack!" off the bat, the ball arced into the second deck beyond right field, and Harper paused for a moment to watch his shot before sprinting around the bases.
"Early on, he's hacking. I think he's one of the highest-percentage (hitters) early on, so you kind of know that and you're making pitches," Floyd said, "and my cutter didn't cut like I wanted it to."
That gave the Nationals 11 homers in their last four games, 15 for the season. The 14 entering Wednesday were a franchise record through a season's first seven games.
Floyd struck out the next two batters, but then got into more trouble, giving up Desmond's double and Espinosa's single that gave Washington a 2-1 lead.
Every Nationals starting position player reached base at least once; the only one without a hit, Kurt Suzuki, walked three times.
"It's a tough lineup," White Sox manager Robin Ventura said. "And when you get to that fifth or sixth inning, it's hard to get through it again."
NOTES: Rios' four-game homer streak ended. ... A smattering of applause from the crowd of 24,586 greeted the first announcement of Dunn's presence in the White Sox lineup. He played in Washington in 2009 and 2010. ... Chicago 2B Gordon Beckham sat out after hurting his left wrist Tuesday. He's not sure how long he'll be sidelined. Jeff Keppinger started at second Wednesday, with Conor Gillaspie at third. ... White Sox pitching coach Don Cooper is still hospitalized with a stomach illness.
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