NEW YORK -- Things about the injury to the right forearm of Mets reliever Matt Wise: It is more serious than the club first thought, and it isn't a bruise as the club announced Tuesday. It is a strain. And one more thing: It's serious enough that Wise has been assigned to the disabled list.

The assignment was made on Tuesday, retroactive to April 2, the day after Wise surrendered the walk-off home run to Robert Andino in the Mets' 5-4 loss to the Marlins. The club recalled right-handed reliever Carlos Muniz from its Triple-A New Orleans affiliate to take Wise's place. Muniz pitched the ninth inning of the Mets' 5-2 loss to the Phillies on Tuesday.

Wise said Tuesday the injury was a strain, and he still has no idea how he injured his arm. But he knows the strain restricts his ability to throw his most effective pitch, his changeup. He was examined via MRI on Thursday -- no structural damage was detected -- and examined again Monday.

Wise had a 3-2 record with a 4.19 ERA and one save in a career-high 56 appearances with the Brewers last season before signing a $1.2 million, one-year contract with the Mets in December.

"To me, I was looking forward to him being a big part of our bullpen," manager Willie Randolph said. "But let's get him better as soon as we can."