WASHINGTON (AP) -- Ryan Zimmerman's line drive to right-center kept going - and going and going - until it landed in the first row.
''I just thought it was a double,'' the Washington Nationals third baseman said.
The way the Nationals are playing lately, everything seems to come with a bonus. On a Fourth of July when the ball carried well, they took advantage of a morning start against a weary West Coast team and pounded Madison Bumgarner and the San Francisco Giants in a 9-4 victory Wednesday.
''Another fun day for the skipper,'' Washington manager Davey Johnson said. ''You've got to tip your hat to the offense.''
The Nationals have been carried to the top of the NL East by their pitching, but they put up a 9-spot on the Giants for the second straight day and are averaging nearly seven runs in their last 10 games.
''There's no way that this offense was going to be cold all year,'' starter Edwin Jackson said. ''It was just a matter of time.''
Jackson (5-4) allowed three runs in another rough first inning, the kind of setback the Nationals had trouble overcoming early in the season. He settled down and gave up only one more run and lasted 5 1-3 innings in the midday heat. Three relievers combined to shut down the Giants the rest of the way.
Zimmerman has spearheaded the offense's resurgence, batting .386 (17 for 44) since receiving a cortisone shot in his sore right shoulder on June 24. He was in a 5-for-49 slump at the time, and the travails of the team's No. 3 hitter were becoming a concern in a mostly positive season.
''I was playing banged-up for a while there,'' he said. ''And when you try to play through things, sometimes it doesn't allow you to do the things you've been doing and that leads to other things and other things. It's definitely a lot better when you show up to the park and you feel healthy every day.''
Zimmerman hopes he won't need another shot this season. He's certainly getting plenty of mileage out of this one.
He drilled a line drive his first time up - but it turned into an out when Bumgarner made a nice slide in the grass to retrieve and throw the ball after it hit the pitcher in the leg.
No one got in the way of Zimmerman his next two times up. His double peppered the left field wall - only a few inches from a home run - in a three-run third, and he and Michael Morse hit back-to-back opposite-field homers in a three-run fifth. Zimmerman is now 10 for 20 with four homers and 13 RBIs in six Independence Day games.
Bumgarner (10-5) followed last week's one-hit shutout of the Cincinnati Reds with one of his rockiest outings. He was done after five-plus innings and gave up three home runs, matching a career high. He allowed seven runs total, more than in his previous four starts combined.
''Guys have days like this all the time,'' Bumgarner said. ''It just depends on how good you can minimize the damage. I didn't really minimize it today.''
Washington goes for the sweep Thursday. The Giants have lost four of five and have allowed nine-plus runs in consecutive games for the first time since 2009.
At least, for the Giants, the final game of the series will be at night. Wednesday's first pitch came at 11:08 a.m. so everyone could get home in time to celebrate the holiday, and it came after a Tuesday game that ended late because of a rain delay.
''You travel across the country and get acclimated to the time change and then have to bounce back to play an early game like this. Sure it played a part,'' San Francisco manager Bruce Bochy said. ''But it's part of the schedule and you deal with it. Like I said, we did what we wanted to do by getting on the board early. We just couldn't hold it.''
NOTES: The Nationals are 15 games above .500, matching their season high. ... Washington returned C Sandy Leon from rehab, reinstated him from the 15-day disabled list and optioned him to Double-A Harrisburg. ... Matt Cain starts for the Giants on Thursday, Ross Detwiler for the Nationals.