PORT ST. LUCIE, Fla. -- With nearly six full weeks to go before Opening Day, Daniel Murphy is unconcerned about the midsection injury keeping him off the practice field.

Murphy received a cortisone injection Tuesday in New York to reduce inflammation in what Mets doctors diagnosed as a strained right intercostal muscle. He does not expect to participate in baseball activities for a few days.

In the interim, Murphy plans to ice his right side and ride a stationary bike.

"I'm going to have to be smart," Murphy said. "Hopefully it shouldn't take too long before I can start swinging the bat. But I can't go out there the first day and take 250 hacks."

Murphy will not take the field when the Mets open Grapefruit League play Saturday against the Nationals, and he may miss several more games after that. But considering the regular season does not start until April 1, he is hardly worried.

David Wright and Scott Hairston both lost significant time last spring with similar injuries, and both made it back in time for Opening Day.

"I'd rather miss Spring Training time than miss time during the season," Murphy said. "It's a little frustrating to be hurt, to be injured a little bit right now, but better to be smart now than to miss a game April 15."

Upon returning from New York, Murphy made it a point to speak with Wright, who also received a cortisone injection last year. The third baseman advised him to let the medication take its course, and not to test his muscles -- no matter how tempting it may be -- with any swinging or twisting motions.

Entering his second season as the club's starting second baseman, Murphy hit .291 last year with six home runs in 156 games. He recently avoided arbitration with a one-year, $2.9 million deal.

Collins giving Nieuwenhuis big chance at leadoff

PORT ST. LUCIE, Fla. -- When the Mets take their first hacks of the Grapefruit League season this Saturday, Kirk Nieuwenhuis will be the man digging into the batter's box. There's a decent chance he could draw the same assignment in April.

Manager Terry Collins said Wednesday that he is giving Nieuwenhuis first crack at leadoff, because he sees him as a potential solution at that spot.

"I think it sends a huge message to him," Collins said. "It's the first game. And when we were playing really, really well [last year], that guy was in center field. He deserves the right to get the first shot."

Nieuwenhuis figures to crack the Opening Day roster in a center-field platoon with Collin Cowgill, who possesses the skill set necessary to lead off against left-handed pitchers. Ruben Tejada is the incumbent option at leadoff for the Mets, though they are not necessarily sold on him in that spot. Mike Baxter and Daniel Murphy could also fill the role.

But with six weeks left in camp, Nieuwenhuis may be the favorite. He hit .264 with five home runs in 32 games as a leadoff man last year, compared to .242 with two home runs in 59 games elsewhere.

"Obviously it's a compliment, for sure," Nieuwenhuis said of his manager's curiosity. "I'm hopeful to take this spot and run with it. You set the tone for the game, and it's a big responsibility. You just have to be aggressive and smart. That's the biggest thing."

Thing is, Nieuwenhuis will not need to take the opportunity and run with it -- at least not literally. Collins said he does not need or expect his leadoff hitters to steal bags, so long as they make smart baserunning decisions whenever possible. That is good news for Nieuwenhuis, who had never been an elite base-stealing threat despite his above-average speed.

If Tejada hits leadoff, for example, Collins said he will not have the green light to steal whenever he wants. It stands to reason that Nieuwenhuis, Cowgill and Baxter will not, either.

"When the word 'baserunning' is talked about, everyone thinks it's basestealing, and it's not," Collins said. "We need to go first to third. We need to score from second, no matter who it is."

Mejia cleared to join Mets at spring camp

PORT ST. LUCIE, Fla. -- Major League Baseball has affirmed Jenrry Mejia's age and identity, a Mets spokesman said, clearing Mejia to report to camp in Florida this week.

The United States consulate in the Dominican Republic recently flagged Mejia for what the Mets believed to be a "random" age and identity review. MLB undertook the inquiry, officially clearing Mejia on Wednesday.

Mejia, 23, has been working out in the D.R. while he waited for MLB to complete its investigation. The Mets intend to use him as a starting pitcher this spring, and the right-hander is a strong bet to open the season in Triple-A Las Vegas' rotation.