According to Triple-A Las Vegas manager Tony DeFrancesco, Mets RHP Corey Oswalt was placed on DL, per Las Vegas Review Journal's Betsy Helfand.
Oswalt has been dealing with lat tightness recently, and it appears to be too much to pitch through. The righty made one appearances for the Mets this season, tossing 4.2 innings where he allowed two earned runs on two hits while striking out four.
With Las Vegas this season, Oswalt owns a 6.18 ERA over six starts.