PHILADELPHIA - Matt den Dekker has wasted little time in seizing his chance to earn regular playing time.

In his first two games as the Mets' primary leftfielder, den Dekker has gone 3-for-8, including a tying RBI double in Monday's 5-3 win over the Phillies. And if not for a pair of sparkling defensive plays, den Dekker would have had two more hits.

It's the product of a revamped swing and stance. "I'm just trying to do the same stuff I was doing in Vegas," said den Dekker, who was recalled from Triple-A Las Vegas on Friday. "I'm not trying to change anything."

Den Dekker earned his chance partly by cutting down on his high strikeout rate.

Bad break

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Jeremy Hefner has reached a crossroads in his career. An exam Monday revealed that he has reinjured a ligament in his right elbow in addition to suffering a fractured right forearm, derailing his rehab from last August's Tommy John surgery.

The diagnosis came after Hefner, 28, was shut down with forearm soreness. He had been pitching in minor-league games in hopes of returning this year.

Hefner is weighing his options, which include another elbow procedure, according to assistant general manager John Ricco. Before being shut down last season, Hefner was 4-8 with a 4.34 ERA.

Extra bases

Daisuke Matsuzaka threw three innings in his rehabilitation start for St. Lucie Monday night. He threw 39 pitches, 21 for strikes, and allowed no runs, one hit and no walks, striking out three. Matsuzaka (right elbow inflammation) likely will need two or three more rehab outings before he's ready to rejoin the Mets. Manager Terry Collins said the club wants him to build up his arm strength so he can make spot starts when needed . . . Collins and closer Jenrry Mejia met behind closed doors. Their talk came one day after Mejia made public that he's been pitching through a sports hernia that will require surgery at season's end.