KANSAS CITY -- Left-hander Gio Gonzalez threw six shutout innings and Ryan Zimmerman delivered an RBI double as the Nationals held off the slumping Royals, 2-0, at Kauffman Stadium on Monday night.
Gonzalez gave up just four singles, while walking two and striking out one as the National League East-leading Nationals won their fourth straight and maintained their 1 1/2-game lead over the Mets, who also won on Monday night.
The Royals lost for the sixth time in seven games and have been shut out in three of their last four. In the six losses, they have scored seven runs.
"We have a great offense," Royals left-hander Danny Duffy said. "They have carried us in the past and they will carry us again.
Added first baseman Eric Hosmer, "We didn't really go through something like this last year, so it is kind of odd. But it's early. We're not going to get too worried in May."
Royals right-hander Edinson Volquez survived a shaky two-run first inning and settled down to shut out the Nationals over the next 6 2/3, with Duffy coming on to fan Bryce Harper with two out in the scoreless eighth. Volquez gave up seven hits and struck out seven.
• Volquez, Duffy add silver lining

Daniel Murphy, who went 3-for-4 with an RBI for the Nationals, got his 1,000th career hit in the sixth inning.

MOMENTS THAT MATTERED
Gio-logy 101: Gonzalez needed 28 pitches to get through the first, but ended up throwing six shutout innings and lowering his ERA to 1.15. The Royals' best chance to score off that Nats' lefty came in the sixth. They had runners on first and second with one out, but Alex Gordon flied out to right fielder Harper and Salvador Perez flied out to center fielder Michael Taylor to end the threat.
"Gio was great. He made some pitches when he had to," Nationals manager Dusty Baker said. 'When he was in trouble there, he dug deep. He got the fly balls when he needed to."

A very, ahem, curious steal attempt: The Royals also had some chances early on against Gonzalez, and one came in the third inning. With two out, Lorenzo Cain recorded Kansas City's first hit with a sharp single to left. Then, the red-hot Hosmer walked. That brought up Kendrys Morales, who missed a homer in the first inning by a foot or so. But Cain went against convention and tried to steal third with two out and was thrown out easily by Nationals catcher Jose Lobaton.
"It's a spot where you can't afford to be thrown out," Royals manager Ned Yost said. "But our team, we love to pressure defense. There are so many ways you can score from third base with two outs. He was just trying to create an opportunity to make something happen.
"We win those situations a lot more than we lose. ... It didn't work out for us tonight, but it normally does."

The Nats score first: The Nationals gave Gonzalez a 2-0 lead before he threw a pitch. Taylor led off the game with a walk, took second on a single by Anthony Rendon and scored on a one-out double by Zimmerman. Rendon scored a second run on a groundout by Murphy.
"We beat a very good club over there with outstanding pitching," said Baker. "We have to keep rolling."

Sal the sheriff: Royals catcher Salvador Perez continued to mow down would-be basestealers. Harper tried to steal second after leading off the sixth with a single. Perez's throw just beat him, though Harper signaled to the dugout for a review. Replays showed the tag indeed beat him, and the Nationals passed on going to the headsets. Perez has nailed 11 of 18 (61 percent) of attempted basestealers this season.

QUOTABLE
"It's crazy how it is when the manager lets you pitch more than three innings. It's unbelievable when your manager believes in you so much." -- Gonzalez
BRYCE'S EARLY MAY SLUMP
Harper, the NL Player of the Month for April, went 1-for-4 with two strikeouts on Monday, after going 0-for-4 with four K's on Sunday.
• Hot start earns Harper NL Player of the Month

VIDEO SYSTEM ISSUES
The Nationals' video system went down in the top of the third inning. Baker was wondering how to move forward. By the time the umpires talked to officials at the Replay Command Center in New York, the video system was up and running again.
WHAT'S NEXT
Nationals: Right-hander Tanner Roark (2-2, 2.03 ERA) makes his sixth start of the season at 8:15 ET on Tuesday night against the Royals. He hasn't been scored upon in his last 14 innings and has 21 strikeouts during that stretch.
Royals: Right-hander Chris Young (1-4, 6.12 ERA) takes the hill on Tuesday night in a 7:15 CT start. Of the 17 runs Young has allowed this season, 11 have come on home runs.
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