HOUSTON (AP) -- Houston starting pitcher Brett Oberholtzer ended April in a way he would like to forget.
The left-hander, who had four strong starts to begin the season, ended the month with two poor outings, including Wednesday night against Washington.
Anthony Rendon had four hits, Jordan Zimmermann pitched smoothly into the seventh inning and the Nationals beat the Houston Astros 7-0.
Oberholtzer allowed a career-high tying six runs on a career-high 11 hits with three walks and five strikeouts in 4 2-3 innings.
"I don't think I got away from pitching inside," Oberholtzer said. "I think I threw the ball well to the outer third of the plate today against the righties; the changeup was on. I thought I threw the ball well, some ground balls went through the hole. I got some tough breaks."
The left-hander has struggled in his last two starts, allowing 12 runs in 8 1-3 innings. His last two starts have been the only starts of his career that he failed to reach five innings pitched after throwing five innings in each of his first 14 starts, which tied a franchise record.
"It's frustrating losing," Oberholtzer said. "This is the big leagues. We need to come out ready to win. We are not going to beat anyone on a day to day basis with our talent, but we have to be willing to come out here and compete harder on a day to day basis and matching the intensity the other teams bring to the game. We have to bring it every day."
Houston manager Bo Porter said it looked like Oberholtzer has gotten away from pitching over the inner third of the plate in his last couple of outings.
"When you get predictable to one side of the plate, Major League hitters are going to take advantage of that," Porter said. "He left some balls up. When you look at the success that he had last year, it was because of the ability to pitch to both sides of the plate. Right now, it's all to one side of the plate."
Guzman had three hits, and Jonathan Villar finished with two hits for Houston.
"We didn't generate much offense, and when we did we just could not get that big hit," Porter said. "At the same time, when a guy shuts you out, you know that he's throwing the ball really good."
Rendon connected for a two-run double in a four-run fourth and added a solo home run in the sixth. The Houston native added a double in the first and a single in the third but flew out to left in the eighth.
Zimmermann (2-1) scattered seven hits in 6 1-3 innings. He struck out seven to earn his 45th win with the Nationals, making him the winningest pitcher since the Montreal Expos moved to Washington in 2005.
Denard Span and Kevin Frandsen each had two hits and Danny Espinosa also had two hits, including a solo home run in the fifth that chased Brett Oberholtzer (0-5).
Span put the Nationals up 1-0 in the third with a triple to center field, and he scored on an error by George Springer.
Frandsen extended the lead to 2-0 in the fourth, scoring on Jesus Guzman's error after advancing to third on Sandy Leon's single. After Rendon's double, Jayson Werth singled to score the third baseman.
NOTES: Porter said the rotation against Seattle would be Brad Peacock on Friday, Dallas Keuchel on Saturday and Collin McHugh on Sunday. . Houston pitcher Scott Feldman, who has been on the disabled list retroactive to April 18 with right biceps tendinitis, is going to throw a simulated game on Sunday and "then we'll go from there," Porter said. "Feldman has had a lot of time off and we just wanted to give him a couple of extra days to continue to get built up and then we'll slide him back in accordingly." . Washington first baseman Adam LaRoche was out of the lineup Wednesday with a quad injury. "He did it last night running to second on the double," Washington manager Matt Williams said. "I didn't want to take him out of the lineup but it's probably better to give him two. We're trying to get him as much rest as we can and try to calm it down a little bit."
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