Adam LaRoche slides safely into third during the second inning. (Lenny Ignelzi/Associated Press)

Wednesday evening, as clouds rolled over Petco Park, the Washington Nationals found a new way to win. Tom Gorzelanny concealed his smile after he smacked an RBI single on his way to a three-inning save. Starting pitchers kicked their feet up on the dugout railing. Hitters bumped fists at the helmet rack. Manager Davey Johnson sat back on the bench.

The Nationals had built the National League’s best record on a steady diet of incredible pitching, one-run leads, antacid pills and chewed-off fingernails. Wednesday, they could finally relax with a 7-2 victory over the San Diego Padres, their largest margin of victory during an unprecedented, unexpected and unbelievable start.

After Jordan Zimmermann’s stellar performance and an unusual outpouring of support for him, the Nationals had another series victory in their back pocket, 6 for 6 this year. They have a 14-4 record, the best start in Washington baseball history, matched only by the 1932 Senators. This laid-back victory put all the others — 13 decided by four runs or fewer, eight decided by two or one — in perspective.

“Not that we can lay down late in the game,” first baseman Adam LaRoche said. “But it’s nice to know every pitch, every play isn’t a potential loss. If we keep flirting with these one- and two-run games, one pitch, one base hit and we can lose. It hasn’t happened. And it’s been awesome.”

If the Nationals wanted to add another nip-and-tuck win, Zimmermann made it possible. He allowed one run in six innings on four hits and no walks to go with six strikeouts, which actually raised his ERA to 1.33, which ranks no better than third among Nationals starters.

“For me, I always want to try to do better than the guy before,” Zimmermann said. That would not be a problem on most staffs. But he follows Gio Gonzalez, who has a 20-inning scoreless streak. And Gonzalez follows Stephen Strasburg.

Before he allowed a home run in the fifth, Zimmermann extended the Nationals’ starting rotation’s scoreless streak to 26 innings, their longest such stretch since baseball returned to Washington. In 14 of 18 games this season, their starters have allowed two or fewer earned runs.

“They’re trying to compete against each other when they’re going out there,” Johnson said. “It’s been fun to watch.”

The difference Wednesday was, without Ryan Zimmerman but against the rancid Padres (5-14), the Nationals didn’t need a great start. LaRoche went 3 for 3 with a walk, raising his on-base percentage to over .400 while producing his team-leading 14th RBI. The Nationals turned a one-run game into a blowout with a four-run seventh, paced by Wilson Ramos’s two-run, bases-loaded single.

The Nationals could lose Zimmerman for another week. They have played all season without cleanup hitter Michael Morse and closer Drew Storen. It hasn’t mattered.

“Whatever adversity is thrown at us, it seems like we’re handling it pretty well,” shortstop Ian Desmond said.

Wednesday, the Nationals afforded Zimmermann the unknown luxury of early run support. In his first three outings, the Nationals scored one run while Zimmerman was still in the game. In the second inning, LaRoche and Rick Ankiel both doubled down the right-field line for the game’s first run.

With two outs and Ankiel on third, Padres starter Joe Wieland intentionally walked Roger Bernadina to pitch to Zimmermann. A career .176 hitter, Zimmermann ripped a single up the middle to score Ankiel. He had made seven starts without pitching with a two-run lead, but now he had one. It made a difference.

“Definitely,” Zimmermann said, smiling wide. “It’s pretty nice. In a big ballpark like this, if you get behind on someone, you can groove something over the middle and let them put it in play and try to get themselves out.”

Staked with a lead to protect, Zimmermann dispatched Padres like chaff through a threshing machine. He retired 14 of the first 15 batters he faced, mixing 93-mph fastballs with power sliders and snapping curveballs. Yonder Alonso’s double in the third was his only blemish. Zimmermann threw two strikes for every ball, and his efficient dominance made his first career complete game a vivid possibility.

“I just felt really good,” Zimmermann said. “Wilson and I were on the same page. Every time he put it down, I felt confident.”

Then in the fifth, Zimmermann hung a 1-1 curveball to Orlando Hudson, a 34-year-old hitting .196 with no homers. Hudson clobbered the pitch to the right field seats. The starters’ streak of scoreless innings had been snapped, and the Nationals had allowed only their fourth homer of the season. More urgently, a lead that seemed comfortable turned into another one-run nail-biter.

Zimmermann took the mound for the sixth having lost a touch of the command that allowed him to cleave through the first four innings. Pinch hitter Jesus Guzman led off with a bloop single. With two outs, Chase Headley singled up the middle, giving the Padres two runners on base for the first time.

Zimmermann’s pitch count had climbed to 78. Left-hander Jeremy Hermida stood at the plate while Gorzelanny warmed up in the bullpen. Pitching coach Steve McCatty visited Zimmermann on the mound. “Focus,” he told him.

Zimmermann threw two fastballs and then a change-up, the pitch he developed this spring, and Hermida fouled it away. Zimmermann followed with a 94-mph fastball. Hermida swung through it, and Zimmermann walked off the mound for the final time of the afternoon.

He led by one at that point. As Zimmermann watched the Nationals pile on more runs, no one had to sweat. “Everyone is more relaxed,” he said. In the bullpen a few relievers tossed just to get work in. In the clubhouse, one player yelled from the weight room, “Yeah, baby!” The margin of victory had made them relaxed, sure, but the result still mattered most.

“I mean, 14-4, that’s grooving,” Desmond said. “You don’t get any extra points for beating the guys by 15. We’re just playing to win. It’s fun.”