The 39-year-old winger has four goals and five assists in 49 games with the Islanders this season.
Rolston has scored 339 goals and 407 assists in 1235 career NHL games with the Devils, Bruins, Wild, Devils and Islanders.
He was originally selected in the first round (11th overall) of the 1991 NHL Entry Draft by the New Jersey Devils.
Rolston is in the final year of a four-year deal he signed in 2008 worth an average annual value of $5,062,500.
Mottau has registered two assists in 29 games for the Islanders this season.
He has scored seven goals and added 51 assists in 307 career games between the Islanders and Devils.
The defender is in the final year of a two-year deal worth an average annual value of $800,000. He will become an unrestricted free agent at season's end.