Sunderland manager Roy Keane has urged the club's fringe players to be patient and is adamant he will need them at some point this season.

Injuries and suspensions left the Wearsiders short on numbers last season and Keane says strength in depth is key to the club's top-flight ambitions.

"For a club like Sunderland the importance of substitutes is enormous," he told BBC Radio Newcastle.

"We'll get nowhere with just 11 players - we need a squad."

Keane also expressed his delight at Michael Chopra's two-goal return in the win over Middlesbrough on Saturday, having backed the striker to bounce back from his off-the-field problems.

"I spoke to the media on Friday and said Chopra looked back to his old self, and we had a training session where he looked really sharp," he said.

"He's had a difficult time, not just off the pitch but the suspension didn't help.

"But he's a fox in the box, he was lively and as well as scoring the goals, the keeper made another couple of saves from him."

Newcastle-born Chopra joined Sunderland from Championship side Cardiff City in July 2007 for a fee of �5m and has made 36 appearances, scoring eight goals.