Arca set for new role
By Rob Lancaster
Last Updated: 01/01/70 1:00am
The 22-year-old will now be in the squad for the game against Preston at the weekend with the former Republic of Ireland manager looking to revert the player back to his natural position.
"He's been terrific all pre-season and he'll definitely be involved in the squad on Saturday," the Black Cats boss told the club's website.
"From my point of view, I watched him from afar and saw him as a wide left midfield player. Having sat down with him, his actual position is left back."
Arca has been in and out of the starting XI at the Stadium of Light and will look to establish himself in a more familiar role.
"I didn't buy him, I wasn't involved in that process, but he played wide left for a long time - I know because I kept watching Sunderland as Irish manager and he was keeping Kevin Kilbane out of the team."
McCarthy added: "But he's played more at left back, he's trained at left back and he played there for the reserves and did well."