Sunderland have stepped up their interest in Wigan Athletic midfielder Lee Cattermole by tabling a formal offer.

Press Association Sport understands the the Wearsiders have followed up former Latics manager Steve Bruce's interest in the 21-year-old by submitting an undisclosed offer.

Wigan chairman Dave Whelan insisted earlier in the summer that the England U-21 international was not for sale, and it remains to be seen if he can be prised away from the club he joined from Middlesbrough last summer for £3.5m.

Sunderland manager Bruce is already hoping to push through his first summer signing over the weekend, after agreeing a fee with Manchester United for Fraizer Campbell.

It is understood the Premier League champions have accepted a bid of around £5m for the young forward, who has been courted by Hull City in recent weeks.