Sydney FC coach Graham Arnold is looking to sign tougher, stronger and more physical players in the January transfer window as a result of the bruising nature of A-League football.

With three players already out for the season with serious knee injuries and another set to play Wellington Phoenix on Sunday with 10 stitches still in his forehead, Arnold revealed physical presence is becoming the main quality he's looking for in his potential injury replacement signings.

Enforcer: Graham Arnold has decisions to make on recruits. Credit:Getty Images

The Sky Blues can sign up to three players to cover for the injured Ali Abbas, Nick Carle and Corey Gameiro and have two foreign player spots available. With plenty of options but limited funds within the A-League salary cap, Arnold will likely use at least one of those places on a player whose primary attribute is winning the physical battles on the field.

"Maybe a couple of players coming in that can add a lot of physicality to our game instead of us just relying on quality," Arnold said. "No closer, getting phone calls and emails all the time. There are plenty of names being put forward but we only have a certain amount of money to spend on injury players and they're not cheap. I said, I want to bring quality to the club, if not I'd rather play Australian kids."