SAN FRANCISCO What task was tougher Tuesday night? Taming the Washington Nationals snarling lineup, or scratching some runs off N.L. ERA leader Jordan Zimmermann?Madison Bumgarner used the snare, the whip and his biting stuff to keep the Nationals at bay while tossing his second career complete game. And Brandon Belt did the rest, missing a two-home run night by a combined three feet -- and getting thrown out on the bases twice by a slightly bigger margin -- as the Giants took a 6-1 victory at AT&T Park.This was a feel-good win, and not just because it was the Giants first in five tries against the National League's top team.Belt provided relief, frustration and some head-slapping comedy all in one dose. And then he did it again.He was thrown out at third base after doubling in a run with a shot just below the top of the left field wall in the second inning. Unbelievably, he ran into another out in the sixth when he tried to stretch a single that struck the bricks a few inches below the top of the right field arcade.Belt might have run the Giants out of bigger innings, but all was forgiven -- especially since he has five multi-hit games in the past nine days. After hitting .186 in July, Belt is a sizzling 17-for-36 in August.Zimmermann lost for the first time since June 22 at Baltimore, nine starts ago.Starting pitching reportBumgarner (13-7) didnt own a complete game entering this season. Hes got two now.He held the Nationals to five hits and a run while throwing 74 strikes among his 108 pitches.It was quite an improvement over the fireworks extravaganza that the Nationals set off against him on July 4. Back then, Bumgarner gave up three homers on the way to seven earned runs -- both season highs -- in five innings.Bumgarner let his home dimensions work to his advantage this time. But he had swing-and-miss stuff, too.Slinging hard fastballs and sliders from his easy, three-quarters delivery, Bumgarner faced the minimum over the first three innings. Then he kept his poise in the fourth after the Nats threatened with a leadoff single and a sacrifice bunt that Bumgarner mishandled while failing to record an out.The left-hander recovered against the middle of Washingtons lineup by inducing soft outs in the air from Ryan Zimmerman and Jayson Werth, then the pitcher handled Adam LaRoches comebacker to the mound to strand both runners.The Nationals barely threatened again.Bullpen reportSergio Romo warmed up in the bottom of the eighth and Jeremy Affeldt got loose in the ninth. What more do you need to know?At the plateZimmermann (9-7) entered with an N.L.-best 2.35 ERA and led the league with 20 quality starts, including 12 of the last 13.But the Giants worked him in almost every inning. It took a diving play from first baseman Adam LaRoche on Pablo Sandoval to strand two runners in the first inning.The Giants threatened again in the second after Hunter Pence singled and Belt drove a pitch the opposite way that hit two feet below the top of the left-field wall. Pence scored easily but Belt was thrown out as he tried to stretch his double.Zimmermann showed why hes become one of the leagues top pitchers in the fifth, after Angel Pagan singled and Marco Scutaro followed by executing a hit-and-run single to put runners at the corners. But this was Zimmermanns forte; the right-hander entered with a .140 opponents average with runners in scoring position -- the stingiest mark in the N.L.Incidentally, three Giants Bumgarner (.168), Ryan Vogelsong (.181) and Matt Cain (.185) ranked second through fourth in the league in that department.Zimmermann set up Melky Cabrera with a series of inside pitches that the major leagues hits leader pulled foul. Then Zimmermann came back with a 1-2 pitch in the dirt that Cabrera couldnt lay off, ending the inning.But Belt saw the ball well all night, and he came up in another RBI spot in the sixth when Sandoval walked and Pence lined a one-out single. This time Belt turned on a pitch and sent it soaring just a few inches below the top of the right field arcade -- making him less than three feet removed from a two-homer night.Sandoval scored to give the Giants a 2-0 lead but unbelievably, Belt was thrown out on the bases yet again. This time he paid for admiring his shot down the first-base line, and was thrown out at second base.Brandon Crawford followed with a deep fly out to right field that wouldve scored Pence if there were just one out.Zimmermanns night ended with Belts second RBI hit. It was only the second time all season that he didnt complete six innings. He still hasnt allowed a home run to the Giants in six career starts and 36 23 innings, though.Cabreras double touched off a four-run outburst in the eighth against Nationals right-hander Drew Storen. Sandoval hit a sacrifice fly and Belt came through again, grounding an RBI single through the right side. This time, Belt got to stand on a base, too.Then the Giants borrowed a bit from the Nationals' playbook from Monday night, scoring twice more on infield singles to break the game open.Belt tied his career high with three RBIs (done six other times). Meanwhile, Pence had his first three-hit game as a Giant.In fieldBuster Posey leapt from his crouch to field Jesus Flores tapper in front of the plate in the fifth inning. Just as important, Posey had the presence of mind to remember who was running as he took time to make an accurate throw.Pence did not have his finest hour in right field while trying to chase down Werths triple in the seventh. Pence tapped his chest, making the universal symbol for, My bad.It should be pointed out that shortstop Brandon Crawford had another quietly sensational night with the glove, too.AttendanceThe Giants announced 42,081 paid. Thats a lot of calf-sitters.Up nextThe Giants finish a six-game homestand as well as conclude their season series with the Washington Nationals with a Wednesday matinee. Its a marquee matchup, all right. Tim Lincecum (6-12, 5.35) faces electric-armed right-hander Stephen Strasburg (13-5, 2.90), who probably will make just four or five more starts before the Nationals shut him down as a precaution.