Martinez is 2-2 with a 3.67 ERA in his last four stats - well below his usual lofty standards. His fastball has only occasionally broken 92 mph.
"I feel fine, very strong," Martinez said. "There's no problem in terms of my health."
Martinez (9-3 overall) will face right-hander Kip Wells.
"I would love to have 10 wins before the break but it's more important for us to have some momentum and feel good about ourselves as a team," Martinez said.
Victor Zambrano will start for the Mets on Friday and Kazuhisa Ishii on Saturday.
RHP Pedro Martinez is learning the same hard lesson Tom Glavine has become numb to -- when you take Fred Wilpon's millions to pitch for the Mets, run support is not part of the package.
Martinez allowed three runs over seven innings Tuesday night. But his teammates did even less against Estaban Loaiza as the Washington Nationals beat the Mets 3-2 at RFK Stadium
"Loaiza was just nasty today," Martinez said. "It was a good game from either side."
Martinez (9-3) allowed three runs on eight hits with one walk and six strikeouts. But Loaiza (5-5) was better, giving up one run on six singles over eight innings. He walked one and struck out eight.
"You'd surely like to capitalize on a quality start," Mets manager Willie Randolph said. "Pedro showed the kind of All-Star pitcher he is. I can throw superlatives at him all day."
It was the fifth time this season Martinez has allowed three runs or less and not gotten a victory.
"I just pitch," Martinez said. "I'm just out there to give my team a chance to win. I don't care what goes on with me and the victory."
In his rookie year as manager, Willie Randolph has resisted the urge to tinker with his players and their delicate egos. Better to be patient than panicky, he thought.
There are limits to such tolerance, and Randolph reached his on Monday. With the season in its second half and his team 10 games out of first place, changes had to be made.
Jose Reyes was dropped from first to seventh in the batting order against the Washington Nationals, and Carlos Beltran was second. Mike Cameron moved into the leadoff spot, and Cliff Floyd hit third.
"I wouldn't call it a shakeup. We're just moving things around a little bit," Randolph said. "It's something I've been playing around with in my mind."
In a game the Mets deemed as important as any they played this season, the changes paid off in a 5-2 victory before a sellout crowd of 44,331 at RFK Stadium.
Reyes had two hits, one RBI and scored the go-ahead run in the ninth. Cameron also had two hits and drove in two runs. Beltran added two hits and one RBI as the Mets snapped Washington's win streak at six games.
Randolph said the lineup changes, while effective Monday, aren't permanent. Reyes has a .326 on-base percentage hitting right-handed and will lead off against left-handers. He has hit either first or second for the Mets with the exception of 83 at-bats during his rookie year when he hit eighth or ninth.
Beltran could remain in the second spot. He has hit .290 as a No. 2 hitter over the last three seasons, 29 points better than when he hits third. His on-base percentage and slugging percentage show similar improvements.
"I thought it was a good move," Beltran said. "Hopefully it will continue to work for us."
When the Mets had injuries last season, they all but walked the streets of Queens looking for replacements. A succession of journeymen and rookies dotted the roster.
That changed last winter when they signed Marlon Anderson, Miguel Cairo and Chris Woodward, three capable infielders who would start for many teams.
Anderson and Woodward have been in the starting lineup in recent days, filling in for the injured Kazuo Matsui and Doug Mientkiewicz. Their value was never more apparent.
Woodward had an RBI single in the eighth inning on Friday (July 1) to boost the Mets to a 7-6 victory over Florida. He drove in Anderson, who had doubled to start the inning.
Through 81 games, Woodward was hitting .330 and had 13 RBIs. Already this season he has played first base, second base, third base, shortstop, right field, left field and a few innings in center.
"I carry four gloves," he said. "Just in case."
Anderson was at .275 and leading the majors with 13 pinch hits. He has been Willie Randolph's first choice off the bench in clutch situations.
Cairo, who came off the disabled list on Saturday, has hit .275. Like Woodward, he has played multiple positions.
Their production is what Randolph expected when the trip signed.
"I'm not surprised at all. Those guys are good players, good teammates," Randolph said. "We don't lose much when they're in the lineup."
INF Jose Offerman is 3 for 4 with a home run and three RBI as a pinch-hitter since being called up on June 26. "It's hard being a pinch hitter," he said. "I'm not comfortable doing it. It's hard because you have one chance. You can't afford to wait for a perfect pitch."
INF Chris Woodward was back in the lineup Tuesday, a day after he was taken out of the game with a swollen left knee, the result of a foul ball. X-rays were negative and the swelling went down enough to allow him to play. "I've never had anything swell up that fast," said Woodward, who was 0 for 3. "The knee itself is fine. There's a little pain when I move around but I can play with that."
RHP Braden Looper caught heat from fans when he blew a save against the Yankees on June 26. Looper had converted all three of his save chances through Tuesday since, allowing one hit in three scoreless innings. "You have to turn the page quickly," he said. "Losing to the Yankees was tough but you can't dwell on it."
1B Brian Daubach was 2 for 24 through Wednesday since being promoted from Class AAA Norfolk on June 15. "I'm not getting the job done," he said. "I've been playing a long time and this is as frustrated as I've been."
RHP Roberto Hernandez threw two more scoreless innings Monday. Hernandez (4-2) hasn't allowed a run in his last 14 appearances, dropping his ERA from 2.82 to 1.78. He has pitched 13 innings in that span, allowing eights hits with five walks and 12 strikeouts. Hernandez also hasn't allowed an earned run in 17 2/3 innings on the road this season. "It's been awhile since I had this much fun," Hernandez said. "I'm doing what I did in years past. I'm mechanically sound and mentally sound, too. Once I make a mistake I know what I did wrong and I can correct it before the next pitch."
Having three players selected to the All-Star game will cost the Mets $200,000. Carlos Beltran's $119 million contract includes a $100,000 bonus for each time he makes the team. Pedro Martinez and Mike Piazza will receive $50,000 each.
LHP Kazuhisa Ishii needed 87 pitches to get through 5 1/3 innings Monday. But he allowed only two runs on five hits and will likely retain his spot in the rotation.
INF Miguel Cairo was activated off the disabled list on Saturday. He played in four minor league rehab games to test his strained left hamstring. OF Victor Diaz was optioned to Triple-A Norfolk. He will get work as a first baseman in the minors to try to increase his versatility.
LHP Royce Ring has become the primary left-hander out of the bullpen. "He doesn't seem to have any fear, and his delivery has a little funk in it," manager Willie Randolph said. "We want to see what we have in him."
1B Doug Mientkiewicz, on the disabled list with a right hamstring strain, doesn't expect to return until after the All-Star break. "I had never pulled a muscle before, and for a few days I could barely sit down," he said.
RHP Steve Trachsel has been on the disabled list all season after having back surgery in March. He took a significant step in his comeback on Saturday when he threw off the front of the mound. Trachsel's next step will be starting a regular throwing program at the team complex in Florida. He hopes to return to the roster by Aug. 1.
SS Jose Reyes played in only 53 games last season because of a variety of lower-body injuries including a hamstring tear. But he played in 80 of the first 81 games this year, starting 78 of them. No Mets player has been more durable. "I'm finally having some fun," said Reyes, who leads the majors with nine triples. "I'm running like I used to."
BY THE NUMBERS: 1 -- Number of stolen bases Carlos Beltran had prior to June 30, when he stole two in the same inning against Philadelphia.
QUOTE TO NOTE: "If I hit the ball to the gap, I think about a triple right away. You have to run hard to first and take a good turn or you won't get it. I run hard every time." -- SS Jose Reyes, the major league leader with nine triples.