Left-hander Mitchell Parker threw seven shutout innings, and Luis Garcia Jr. had three singles and two RBIs and the Washington Nationals beat the Houston Astros 6-0 on Sunday.

The Nationals have won three of their past four series after starting the season 2-6.

After allowing two runs over five innings last Monday in his major league debut, a 6-4 win over the L.A. Dodgers, Parker (2-0) was even more effective in his second major league start, allowing three hits, striking out eight and walking none, throwing 57 of his 73 pitches for strikes.

“He has so much poise," Nationals manager Dave Martinez said. "He’s ready. He gets the ball, ready to get back on the mound. I watched him today. He threw a ground ball. The play was made and he got right on the mound and was holding his glove up as if, ‘hey, come on, give me the ball, like I’m ready to get back on there’. It was cool to watch. He understands what he wants to do.”

Parker mixed his 85-87 mph splitter, 81-82 mph curveball and 92 mph four-seam fastball. He struck out Jose Altuve and Jeremy Peña a combined four times. Dylan Floro and Matt Barnes each added a scoreless inning for Washington.

Parker was thrilled to be able to throw the splitter for strikes, something that did not come as easy against the Dodgers.

“100 percent, yeah," Parker said. "We were able to get in there for more swings and misses. They were more competitive pitches. Going to keep working on it, seeing if we can keep it where it is at.”

Astros right-hander Hunter Brown replaced scheduled starter Cristian Javier, who was scratched from Sunday’s series finale with neck discomfort. Javier was placed on the 15-day injured list retroactive to April 14, and right-hander Spencer Arrighetti was called up from Triple-A Sugar Land.

Manager Joe Espada said they have not decided yet on an MRI for Javier.

“Neck discomfort, started a few days ago,” Espada said. “He tried to work through it but just couldn’t happen. This kind of just came out of nowhere. So, we are going to see what happens here.”

Brown allowed three runs and three hits and a walk in the first but then settled down, lasting four innings when his pitch count reached 84.

“Even in the first I felt like made some good pitches," Brown said. "Came to the outing prepared. Kind of did what I wanted to and it just didn’t fall our way there.”

García Jr.’s two-run single to center field highlighted the three-run first inning for the Nationals.

“We try to score every inning,' Garcia Jr. said through a translator. "But definitely when we score the first inning it gives you a different kind of sense of confidence throughout the game and it carries on through the games a different feeling.”

Joey Meneses had a bases-loaded two-run single to right field off Shawn Dubin in the fifth to make it 5-0. Nick Senzel hit his first home run of the season in the sixth to close out the scoring.

The Astros' tailspin continues, having lost five of their past six and nine of their past 12.

“It is not ideal in the situation that we are in but we are in this situation,” Espada said. “And we got to fight through this. We have guys in there who are capable of giving us innings and some of them are doing that. We are going back to playing the style of baseball that everyone sees the Astros play. We feel pretty good about the guys that we have in there to get us some good innings."

TRAINER’S ROOM

Astros left-hander Framber Valdez threw again Sunday and has a chance of starting one of the games in Chicago his week. “We will see how he feels,” Astros manager Joe Espada said. “Once we see how he feels, we will start talking about the possibilities if he can pitch in Chicago or not.”

Nationals catcher Keibert Ruiz said he is about “90 percent” recovered from the flu that placed him on the 10-day injured list on April 12. Nationals manager Dave Martinez said Ruiz will go on a rehab assignment this week to play a couple of games before returning to the club.

UP NEXT

Houston travels to Chicago to begin a three-game series against the Cubs on Tuesday. Espada confirmed JP France and Justin Verlander will start two of the games, but did not specify the order. Spencer Arrighetti, who was called up for Javier, is an option for the opener.

Washington has a day off before hosting the L.A. Dodgers on Tuesday night. Left-hander Patrick Corbin (0-3, 8.06 ERA) faces the Dodgers for the second consecutive start.