Pena will be part of the Mets' three-man taxi squad for their seven-game road trip to begin the season, Anthony DiComo of MLB.com reports.
Though Pena wasn't able to secure a spot in the Mets' Opening Day bullpen, he could be the next man up to join the roster if New York should have a need for an extra reliever during its four-game series in Washington and three-game series in Philadelphia. If Pena isn't called up before the road trip ends, he'll likely be assigned to Triple-A Syracuse.