LONDON — Team USA forward Carmelo Anthony said Thursday at practice he has a “tight’’ left hamstring and Knicks trainer Anthony Goenaga was summoned back to London to work with him.

Anthony was hampered by a hamstring injury during parts of last season. Goenaga was with Team USA in London early on working with Anthony before the Olympics began but went back to the U.S. before being called back Monday.

Team USA faces Argentina Friday in the semifinals – considered a very dangerous foe despite the Americans beating them 126-97 Monday in pool play after a tight first half. Anthony got hit in the groin in that game by point guard Facundo Campazzo as he made a 3-point shot, nearly causing a melee. Melo labeled it “a cheap shot’’ that was “uncalled for.’’

Anthony said, however, his groin is OK. Knicks point guard Pablo Prigioni did not play in the last USA game as he was being rested after having a kidney stone. He will play Friday.