HOUSTON — The Mets made roster room for tonight’s starter, Jonathon Niese, by putting Gary Sheffield on the disabled list due to a strained right hamstring.

Although the move is retroactive to July 18 and seemed to be overdue, considering the 40-year-old slugger had been sidelined more than a week, Sheffield was not happy with it.

Sheffield, who testily declined comment when the move was announced just an hour before game time, was seen having an animated conversation with Jerry Manuel in left field for more than 15 minutes during batting practice.