Carlos Lee had a two-run double and three-run homer and Jed Lowrie added a two-run double versus Mike Pelfrey, all in the first two innings, and Houston beat the Mets, 9-5, Sunday afternoon at Osceola County Stadium.

The Mets head into an organization-wide off-day Monday winless in their past nine Grapefruit League games.

Pelfrey, making his third spring-training start, allowed eight earned runs on eight hits and four walks in 2 2/3 innings while tossing 80 pitches (47 strikes). He struck out four batters, after having not fanned any in his first two Grapefruit League outings, which spanned seven innings.

The eight runs allowed by Pelfrey were one shy of his regular-season career high, done twice in 2009, against the Atlanta Braves and Pittsburgh Pirates.

“It’s bad execution,” Pelfrey said. “Obviously I’ve been up a lot. And the ball doesn’t sink when it’s up. The other part is, like Carlos Lee there, it was right down the middle.”

The Mets tendered the arbitration-eligible Pelfrey a contract last offseason. The right-hander then settled with the organization for $5.7 million. Pelfrey is under the Mets’ control through the 2013 season, but will be a logical non-tender candidate next December if he does not improve on last season’s performance, which included a 4.74 ERA and career-high 21 homers allowed.

After registering only 87 mph in his previous outing, Pelfrey said he overthrew the ball Sunday, trying to up his velocity. The staff had asked him to throw harder to get his arm strong for the season.

Pelfrey said he ended up “yanking” his sinker as a result -- meaning he did not get on top of the baseball to drive it downward. Instead, Pelfrey explained, he created more of a Frisbee action by getting on the side of the baseball and not finishing the pitch. It stayed flat and in the middle of the strike zone.

That’s what happened when Pelfrey grooved to Lee a down-the-middle two-seam fastball that was intended to be an inside pitch, resulting in the three-run homer. Pelfrey said he missed the intended target by six inches.

Still, Pelfrey said, he was unalarmed. He typically has horrendous spring trainings. Two years ago, he allowed three homers in a game to the Washington Nationals in Viera. That year, he ended up dominating the Tampa Bay Rays at the Trop in his final spring-training start and then opened the season 9-1.

Pelfrey allowed eight homers and had a 6.15 ERA in 26 1/3 innings during spring training in 2010. He now owns a career 3-14 record and 6.90 ERA in Grapefruit League games. He has had a 5.48 ERA or higher every spring training since 2007.

“Of course I would love to get everybody out,” Pelfrey said. “Every spring training I’ve had, I don’t know if I’ve ever had a good one. So it doesn’t necessarily concern me that much.”

Still, he added: “At the end of the day, I threw 80 pitches. I feel good. Velocity-wise and coming out of my hand, I thought today was the best day. I don’t know how many more starts I have -- two, or three maybe. I know I definitely need to be better than that.

“Results are always welcome. I remember in ’10 getting my brains beat in for five or six starts. And then the last start was at Tampa, and I went six innings, one run. And I started off 9-0 or whatever. I’m not too worried about it now. I feel good. The results will come.”

Pelfrey is due to start Game 4 of the regular season, the opener of the second series, against the Washington Nationals on April 9.

Said Terry Collins: “One of the things we asked Mike to do today was to start to ramp the velocity up a little bit, which he did. … I just thought today Mike reared back and let some fastballs go. That’s a good sign for him. He’s been really working on trying to get a feel for the sinker. And we just said, ‘Let’s start throwing it hard and see if we can get some movement on it.’ He was around the plate. He just couldn’t make a pitch with it.”

• Daniel Herrera, an outside candidate for the lefty specialist role until Tim Byrdak returns, inherited two runners from Pelfrey with two out in the third. He tossed three straight balls to open a matchup with lefty-hitting Travis Buck, but ultimately coaxed an inning-ending groundout.

Likely frontrunner Garrett Olson pitched a 1-2-3 seventh.

Josh Edgin, trying to convince Mets officials to allow him to make the leap directly from Class A to the majors, surrendered a one-out double to lefty-hitting Brett Wallace in the eighth. Edgin wiggled free of the jam by coaxing lefty-hitting Joe Thurston into a full-count flyout to left field for the inning’s final out.

• Ronny Cedeno produced his first Grapefruit League homer, off ex-Met Livan Hernandez. Rob Johnson homered in the eighth. It was only the Mets’ fourth and fifth homers of spring training.

The Mets also received RBI singles from Vinny Rottino and Mike Baxter. Baxter started in center field, a position he needs to demonstrate he can handle as the backup if he wants to unseat Adam Loewen for the lefty-hitting backup outfielder role.

• Ex-Met Fernando Martinez struck out three times and also walked in four plate appearances while starting in left field for the Astros.

• David Wright hit off a tee and against underhand-tossed baseballs in Port St. Lucie.

• Right-hander Jeremy Hefner tossed two scoreless relief innings.

• The Astros are committed to Kissimmee’s Osceola County Stadium for three more years, but there is speculation they will at least consider eventually sharing the Mets’ spring-training complex in Port St. Lucie. The Mets would like another tenant at Digital Domain Park to reduce the amount of travel, and St. Lucie recently put $2.4 million into the facility. New Astros owner Jim Crane owns a golf course in Stuart, not far from the Mets’ complex, fueling optimism the Astros eventually will relocate to the area.