But Tuesday was a different story for Perez. He had his best outing of the season and helped the Nationals blank the Mets, 1-0, at Nationals Park.
Perez lasted 7 1/3 innings and gave up four hits. He struck out six batters and walked none. He felt it was the strongest game he'd thrown all year.
"When I was in the bullpen [earlier in the day], [bullpen coach] Rick Aponte said, 'The ball is coming out of your hands very, very good.' And I took the same approach to the game," Perez said.
Why was Perez successful on Tuesday against the Mets compared to last week? The southpaw felt that the Mets knew what was coming at Shea Stadium, and that he had to hide his pitches a little better.
"Maybe I was tipping my pitches," Perez said. "It could be something they might see in my pitching. Tonight, I said, 'I got to do the same thing I do with every pitch.'"
Perez even helped himself with the bat off starter Mike Pelfrey. With two outs in the fifth inning, Perez doubled past a diving Fernando Tatis in left field. Tatis ended up separating his right shoulder on the play and leaving the game. After Willie Harris walked, Cristian Guzman doubled to left-center field to drive in Perez.
"I'm not saying I'm a good hitter, because I'm hitting .160," Perez said. "I'm lucky to go out there and put the ball in play."
Perez left the game in the eighth inning with runners on first and second and one out. But left-hander Michael Hinckley entered the game and prevented the Mets from scoring.
Jose Reyes hit a chopper back to the mound. Hinckley made a high throw to Guzman, who was able to jump, make the catch and tag the bag for the force out. Hinckley then struck out Ryan Church to end the inning.
Since being called up to the big leagues on Sept. 1, Hinckley has not allowed a run in nine innings.
"Oh, this kid is unbelievable. He has great stuff," Perez said. "I don't think [any]body knows him, and I hope nobody ever knows him because of the way he is throwing the ball. He challenges you. If you don't know him, believe me, he is going to strike you out. The kid's stuff, he is very good."
The Mets had their chance to score in the sixth inning. With runners on first and second and two outs, David Wright hit a line drive that appeared to be over Harris' head in left field. But Harris made a diving backhanded catch to end the inning.
"When I turned, the ball was right in the lights, so I'm kind of like, 'Oh, Oh,'" Harris said. "It came out of the lights, and I was able to make the play. The good thing was, I didn't panic. I stayed with it."
It marked the second time Harris made a great catch against the Mets. On May 15, Harris made the play of the game in the ninth inning. With a runner on first, Church was the hitter. The Nationals outfielders were playing him to pull the ball to right field, but Church hit it near the left-field line. Harris, who was playing left-center field, ran a long way and made a great diving catch for the first out of the inning. The final score of that game was also 1-0, in favor of Washington.
"I'm not watching the other 29 teams, but I think this guy has played the best left field this season," manager Manny Acta said. "It's unbelievable with the type of defense this guy has played for us in left. He comes up with one of those plays every two or three days."
Closer Joel Hanrahan turned in a dominant ninth inning for the save. He threw almost nothing but fastballs, which were clocked in the high 90s, was able to strike out Wright and Carlos Delgado and got Carlos Beltran to hit a fly ball to Lastings Milledge in center field.
Acta thought the ninth was a make or break inning for Hanrahan. Prior to the outing, Hanrahan had given up six runs in his last 4 2/3 innings.
"When you have to come into a ballgame, up by one run, and you have to face Wright, Beltran and Delgado, that is a legit save," Acta said. "That was pretty impressive. We were talking about it in the dugout -- not in front of him. But we were saying this could be a real save that could make or break this kid right here."
Said Hanrahan about his outing: "It's the toughest part of the lineup, obviously. I've had some struggles with those guys this year, obviously just recently in New York. Wright got me for a two-run homer. I just tried to go right after him and not give in. I had to throw to strikes to him, and I was fortunate to sneak one by him.
"Earlier in the year, I probably would have walked him right there. My command hasn't been the best thing all year, but I knew I had to get that first guy. I'm not going to give him a walk. Walks have been what's killing me lately."
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.