Aurelien Collin last played against Columbus Crew SC April 22. (Noah K. Murray/USA TODAY Sports)

Still thin at the center back position, Red Bulls head coach Jesse Marsch doesn’t think Aurelien Collin will be available for action against Toronto FC Friday night.

Marsch said the chances of the veteran defender returning to the lineup was “a little optimistic.”

Collin has been sidelined for four successive games after suffering a strain in his abdominal muscle during practice leading up to the game against Chicago Fire April 29.

“Most importantly we don’t want to put him in a position to get re-injured,” Marsch said after training earlier this week. “But he’s back out here and I think he’ll be in training soon so good positive signs.”

The Red Bulls host Toronto FC at Red Bull Arena at 7 p.m. Friday.