PORT ST. LUCIE, Fla. -- As promised, Yoenis Cespedes' shoulder soreness proved minor enough for him to return to the Mets' lineup this week -- actually Thursday, a day ahead of schedule. Going 0-for-3 as the Mets' designated hitter, Cespedes is scheduled to start in left field Friday against the Nationals.
Thursday, Cespedes again hit second in the batting order in the 3-2 loss to the Marlins. Manager Mickey Callaway hinted earlier this spring that the team's foremost power threat is likely to settle into that spot for good.
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"We have a responsibility to put the best lineup out there that has the best chance of scoring the most runs," Callaway said.
Juan Lagares, who has been nursing a strained left hamstring, will also come off the shelf Friday for his Grapefruit League debut.
Birthday present
Michael Conforto celebrated his 25th birthday by taking soft tosses in the batting cage for the first time since shoulder surgery last summer. For Conforto, who had previously been limited to swinging off a tee, it was a continued progression toward full batting practice.
The Mets have set a May 1 target for Conforto's return, though that date is flexible.

Injury update
An MRI on reliever Anthony Swarzak's leg revealed what he and the Mets suspected: a strained left calf. Swarzak, who could not finish his outing Tuesday after feeling his calf tighten up, said that was the first time he experienced something like that in a game.
"When that happened, I knew it was an issue, but I didn't think it was going to be something very severe," said Swarzak, one of four relievers guaranteed jobs in the Mets' Opening Day bullpen. "And it's not severe, so I'm very lucky."
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Camp battles
While others perhaps generate more hype, Seth Lugo quietly plugs along as he looks to win an Opening Day roster spot. Lugo struck out three over three relief innings Thursday, allowing one run. It's the only run he's allowed in five spring innings.
"I felt really good out there," said Lugo, who dialed his fastball as high as 94 mph and dipped his curve as low as 75. "For me, I know hitters aren't quite used to fastballs right now. I try not to look too much into it, but it means I'm executing pitches. So I'm just going to build off that."

Even if Lugo continues pitching this well all March, it may not be enough for him to earn a roster spot. He is behind at least six pitchers on the Mets' rotation depth chart and, while Lugo makes sense as a bullpen option, Robert Gsellman and Zack Wheeler could also fit in that role. The Mets don't have space for all of them, meaning some will go to Triple-A Las Vegas to stay stretched out as starters.
"That's nothing new for me," said Lugo, who has never made an Opening Day roster despite his 36 big league appearances the past two seasons. "It's the same as every year. I'll go out and do my thing and play hard, and that's all I can do."
Up next
With Cespedes and Lagares in the field behind him, Rafael Montero will start the home half of a split-squad doubleheader Friday for the Mets at First Data Field. Jacob Rhame and Drew Smith, two relief prospects the Mets traded for last summer, will also appear in the 1:10 p.m. ET game, before Callaway and his staff shuttle down to West Palm Beach, Fla., for a 6:05 p.m. ET nightcap against the Astros. Gsellman, who is competing with Lugo and others for a roster spot, will start that one, which will air on MLB.TV and Gameday Audio.