New Sunderland manager Niall Quinn made a losing start to his reign after Coventry City came from behind to win 2-1 in their English second division opener.
Sunderland led after Daryl Murphy prodded in on 52 minutes but then conceded twice in a seven-minute spell.
Trinidad & Tobago's World Cup striker Stern John equalised with a fine curling left-foot strike from the edge of the box before Gary McSheffrey caught the Sunderland defence asleep to score the winner with a deflected shot 12 minutes from time.
Former Ireland striker Quinn is also chairman at Sunderland after his consortium bought a controlling interest.
Sunderland were relegated from the Premier League in May after an awful season that produced just three wins and 15 points. They sacked manager Mick McCarthy in March.
In Sunday's other match, substitute Paul Peschisolido netted in the final minute to salvage a 2-2 draw for Derby County at home against Southampton.
