Nolan McLean, one of the Mets’ top prospects, will be called up to start Saturday’s game against the red-hot Mariners, The Post’s Jon Heyman confirmed. McLean will be taking the rotation spot of Frankie Montas, who has struggled and was moved to the bullpen Tuesday.

After demoting struggling starter Frankie Montas, the New York Mets will call up top prospect Nolan McLean to replace him.

Veteran Frankie Montas will move to the bullpen, manager Carlos Mendoza announced prior to the game. Montas' rotation slot, scheduled to come around next on Saturday, could be filled by someone currently at Triple-A -- perhaps top prospects Brandon Sproat or Nolan McLean,