WASHINGTON -- Junior Guerra has pitched in Mexico, with Wichita in an independent league and in Italy, and he did not pitch at all as a pro in 2007, 2009 and 2010.

The well-traveled right-hander made his way to the nation's capital for the first time in his pro career on July 4 and the native of Venezuela shined.

After throwing eight scoreless innings and allowing two hits on Wednesday against the Los Angeles Dodgers, Guerra allowed just two hits and no runs in 7 1/3 innings on Monday as the Milwaukee Brewers beat the Washington Nationals 1-0 in a game that began Monday morning due to the holiday.

"It feels like he keeps getting better," Brewers manager Craig Counsell said. "In the big spots he seems to step up even more. He really competing out there. It's been fun to watch. Junior carried the load out there big time."

Guerra ran his scoreless innings streak to 15 1/3 innings and he has not allowed a run since June 22 against the Oakland A's. He is now 6-1 with a 2.93 ERA for the Brewers after he made his major league debut last season in three games with the Chicago White Sox.

"We only had a couple of opportunities to score," said Dusty Baker, the Washington manager. "The advantage goes to the pitcher when you haven't seen him before. Until you see (his split finger) you don't fully know what it is like. He threw an outstanding game."

Guerra got the best of Washington starter Max Scherzer, who labored in the second and third innings as the Brewers fouled off several pitches.

"He had a high pitch count in those innings," Baker said.

Will Smith retired two batters in the eighth for the Brewers and closer Jeremy Jeffress, a Virginia native, pitched the ninth for his 22nd save as a light rain fell while the Nationals were held to two hits.

The Brewers (36-46) snapped a four-game losing streak while first-place Washington (50-34) lost for just the second time in nine games.

Guerra made his major league debut at the age of 30 last year. He got out a jam in the sixth as he fanned Wilson Ramos for the third out with runners on second and third.

Guerra fanned seven and walked two while throwing 109 pitches.

Martin Maldonado hit a solo homer to left on a 2-1 fastball from Scherzer in the fifth to give the Brewers a 1-0 lead and it held up. It was just third homer in 61 at-bats this season for Maldonado, who has only 23 in a career that began in 2011.

"It feels good. Especially against a guy that's been pitching the way he has been," Maldonado said of his homer. "Last time we faced him it was the same way. We go up there and compete every pitch. To get a lead off him, especially with the way Junior was pitching, was huge."

The Brewers catcher was also impressed with Guerra. "He's been outstanding. He's out there every five days going deep in games. It's huge for us," Maldonado said.

Scherzer (9-6) gave up one run on four hits with three walks and seven strikeouts. He went six innings and threw 114 pitches before he was lifted for pinch-hitter Clint Robinson, who grounded out after his long drive to right went foul earlier in the at-bat.

Scherzer has allowed a league-high 21 homers this year and many of them are slugged by nonpower hitters. He allowed two homers at Milwaukee on June 24. One was by Keon Broxton, who has just one homer in 64 at-bats this year, and the other was by Kirk Nieuwenhuis, who has five homers in 185 at-bats.

Ryan Braun appeared to have a clean single to center with two outs in the top of the first as the third batter of the game. But Braun was ruled out after Baker pointed out to the umpires that Braun batted out of turn.

Jonathan Lucroy was supposed to bat third for the Brewers. Braun then led off the top of the second after Scherzer was credited with three straight outs in the first since Braun batted out of order.

"It was completely my mistake. It's certainly not a good feeling, but the guys really picked me up after that," Counsell said.

Scooter Gennett had two hits for the Brewers. Washington first baseman Ryan Zimmerman entered the game with a batting average of .154 in his previous 15 games. He was hitless in four trips Monday and made the last out on a grounder back to the mound as his average fell to .215 after he began the year as a .283 hitter in his career.

NOTES: The Brewers' plane landed at about 11:30 p.m. ET on Sunday in Northern Virginia after they ended a series in St. Louis. The first pitch was thrown Monday less than 12 hours later. ... Washington RHP Jonathan Papelbon (right intercostal strain) came off the disabled list Monday and OF Michael A. Taylor was sent to Triple-A Syracuse. Taylor is hitting .225 in 191 at-bats with 64 strikeouts for the Nationals while Papelbon has 16 saves. ... The Brewers selected the contract of INF Will Middlebrooks from Triple-A Colorado Springs and transferred LHP Chris Capuano (left elbow soreness) to the 60-day disabled list. OF Keon Broxton was sent to Colorado Springs after Sunday's game. ... Brewers RHP Zach Davies (5-4, 4.22 ERA) will face Washington LHP Gio Gonzalez (4-7, 4.81 ERA) on Tuesday in the second game of the series. ... After hitting five home runs with a club-record 15 RBIs in the last four games, Washington SS Danny Espinosa entered Monday with 18 homers and 49 RBIs this season. ... Nationals first base coach Davey Lopes was the manager of Milwaukee from 2000-2002.