Jack Ross says Jerome Sinclair is 'hungry to prove himself' after becoming his eighth summer signing.
The 21-year-old has joined on a season-long loan from Watford.
Ross said: "We need more players in the forward areas and Jerome is somebody who fits into that bracket, as he can play in multiple positions across the front line.
“I’m pleased to get him in and he’s at a stage in his career where he needs to play games, so he’s hungry to prove himself and he’s got a big opportunity here to do that.”
Sinclair has struggled to nail a regular spot at Vicarage Road but arrives having played an active part in pre-season under Javi Gracia.
The forward scored in a 3-1 win over Fortuna Dusseldorf last Saturday.
In a statement Sunderland thanked Watford for making a deal happen.
The statement read: "Sunderland AFC would like to extend its sincere thanks to Watford for the cooperation and support they have shown in making the loan deal happen."
Sinclair is expected to feature in a Sunderland shirt for the first time when they travel to Middlesbrough for their final pre-season friendly on Friday night.