It has become such a familiar sight the last five seasons plus one month. With the game on the line and Ryan Zimmerman at the plate the Nationals almost expect their star third baseman to win it for them.

Saturday night was no different. Washington trailed by a run in the bottom of the ninth inning and thousands of visiting fans urged on Philadelphia Phillies closer Brad Lidge. But Zimmerman rendered them all speechless with a three-run rocket shot that landed on the batter's eye beyond the wall in dead center field for a dramatic 7-5 victory in front of a sellout crowd at Nationals Park.

Zimmerman tossed his bat aside and yelled with glee at slugger Adam Dunn watching in the on-deck circle. Dunn said the gesture was to let him know he wouldn’t have a chance to win the game. Zimmerman said he was just laughing at his friend, who earlier in the day learned he would not be dealt away at the Major League Baseball trade deadline.

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For Zimmerman, it was the seventh time since 2005 that he was won a game with a walk-off homer. That is the most in the majors, leading Dodgers outfielder Andre Ethier and Red Sox designated hitter David Ortiz, who have six each.

“I wish I could tell you. I don’t know. I just treat it like any other at-bat,” Zimmerman said of his success in late-game situations. “I try to think that the pressure is on [the pitcher] and not on me. Just put a good swing on it. Don’t try to do too much.”

Dunn said he was trying to think along with Zimmerman while waiting for a turn at-bat that never came. Both of them figured a fastball was coming from Lidge, who suffered his fourth blown save of the season. That homer erased a 5-4 deficit. Carlos Ruiz had singled home the go-ahead run for Philadelphia in the top of the ninth inning off Nats rookie reliever Drew Storen. Washington had led most of the night after scoring the game’s first three runs and was up by two entering the seventh inning.

But Raul Ibanez hit a two-run homer off reliever Tyler Clippard in the seventh to tie it. Storen came on with two outs and a runner at third base in the ninth when Ruiz laced his RBI single into right-center to score teammate Jayson Werth.

“He made the adjustment. Guys of that caliber are going to do that,” Storen said of Ruiz. “That’s just something that you have to learn from.”

The Nats recorded five hits off Philadelphia starter Joe Blanton in the first inning alone and scored three times. Josh Willingham, Roger Bernadina and Ivan Rodriguez all had RBI singles. The Phillies answered in the fourth inning with a pair of two-out singles – the latter an RBI hit by No. 8 batter Wilson Valdez.

Washington starter Ross Detwiler rebounded from a rough first big-league appearance in 2010. After missing the first three-and-a-half months of the year recovering from hip surgery in January, Detwiler didn’t make it out of the fourth inning in a game last Sunday at Milwaukee, giving up five unearned runs with three walks.

He was much better on Saturday night – this time on full rest after just three days between his final minor-league start and the game against the Brewers. Detwiler lasted 5 1/3 innings with five hits allowed and three walks. But the Phillies managed just one run off him, stranding runners on base in every inning. Detwiler also struck out three batters.

“It’s a stepping stone,” Detwiler said of his outing. “It’s definitely not where I want to be. But our team stayed in the game and we ended up winning so that’s a good stepping stone.”

Joel Peralta came on in relief of Detwiler and gave up a solo home run to Ruiz with one out in the sixth inning. That snapped a 14 1/3 inning scoreless string by the Washington bullpen and cut its lead to 3-2.

It took just one inning to extend that lead again. Bernadina led off with a double and Rodriguez followed with a single against Blanton. Ian Desmond then ripped a shot to right field, where Phillies rookie Domonic Brown made a spectacular diving catch. He robbed Desmond of extra bases, but Bernadina scored on the sacrifice fly to make it 4-2.

But Clippard couldn’t make it out of the top of the seventh. A walk to Placido Polanco set up the home run by Ibanez, who pulled a line drive into the Nats’ bullpen in right field to tie the game at 4. It was Ibanez’s ninth homer against Washington in the last two seasons alone.

In the end, though, Zimmerman made the home fans forget all about the blown lead. The Nats (46-58) are now 4-1 on this homestand against National League East rivals Atlanta (59-44) and Philadelphia (56-48) – the division’s top two teams. They have a chance to sweep the Phillies on Sunday when John Lannan (2-5, 5.76 ERA) returns to the big-leagues from Double-A Harrisburg for the first time since June 20.

“We’re playing better defense I think,” Zimmerman said of his team’s recent turnaround. “Obviously, when we went on that month skid where we played horrible we were doing the little things wrong…Now we’re on the right track.”