Manager Ron Washington was excited about meeting with President Bush and even happier about his team's performance.
"What was more fun is winning 13-3," Washington said. "I enjoyed my morning, too."
A night after they were held to just one hit in the final 10 2/3 innings of a 14-inning loss, the Rangers broke open a one-run game by scoring seven times in the seventh. Texas reached the .500 mark for the 19th time this year -- it has gone just 3-15 while at the break-even point.
Gabbard (2-3) was staked to a 3-0 lead before he threw a pitch, thanks to a leadoff home run by Ian Kinsler.
"I wanted to get us off to a hot start -- get someone on base early," Kinsler said. "It definitely wasn't an easy win. It was great to get a win after seeing President Bush. Hopefully, he was watching tonight."
Gabbard, who hadn't won in his last nine starts, was sent down to Triple-A Oklahoma on May 30 and was recalled to start on June 15 against the New York Mets. While he lost 4-2, there were signs he improved.
He allowed three runs and six hits in 5 1/3 innings. He struck out five and walked two.
Luis Mendoza pitched the final three innings to record his first career save.
"It's been a while since I got a win," Gabbard said. "Scoring the runs in the first inning settles me in a little bit."
The seven runs equaled Texas' biggest inning of the season. Their 18 hits were a season-high for a nine-inning game.
"We're rolling right now," Gabbard said. "If we score runs, we're going to win a lot of games."
The Nationals have lost eight of their last 10 home games and 14 of 20 overall.
Mock allowed four runs and nine hits, walking one and striking out eight in six innings in his second major league start.
His first start came on June 8, when he was recalled from Triple-A Columbus knowing that he'd be returned afterward.
On Saturday, he was in the same situation. This time, he replaced Odalis Perez on the 15-day disabled list with shoulder tendinitis. Perez made a rehab start on Saturday night and is expected to be reactivated in time for his next start on June 27.
The Nationals optioned Mock and pitcher Brian Sances to Columbus and purchased the contracts of infielder Pete Orr and pitcher Steven Shell after the game.
Lastings Milledge led off the Nationals fourth with a long home run, his sixth of the year. Washington also added a run in the fourth when Dmitri Young, who had doubled, scored on an infield out by Felipe Lopez.
"To me baseball is like boxing," Nationals manager Manny Acta said. "If I don't hit you, you're going to hit me, and that was basically the case for us today."
It was Ron Washington's second visit to the White House. President Bush is a former owner of the team of the Rangers. "He's a total baseball guy. He knew everything, but I guess as president, you're supposed to know everything," Washington said. ... Rangers OF Milton Bradley did not start for the fourth straight game due to a strained left quadriceps. He pinch-hit in the seventh and singled. ... Nationals C Paul Lo Duca made his first start behind the plate since May 7. He'd been on the DL with a fractured bone in his right hand for six weeks.