Oldham Athletic dumped Sheffield Wednesday out of the FA Cup in the first round with a 2-1 win after extra time at Boundary Park.
Calum Kavanagh put the Latics ahead in the second half, only for Davis Keillor-Dunn to level the match and send it to extra time.
Oldham manager Micky Mellon had to watch from the sidelines after being sent off for appearing to move his head towards Callum Slattery.
Will Sutton's 109th-minute winner was deserved for Oldham, as they punished a passive Wednesday performance in Dave Challinor's first game in charge.
Mike Fondop went down in the area under a challenge from Ashley Maynard-Brewer in the first 10 minutes, and while no penalty was given it resulted in an injury to the Owls goalkeeper with Connal Trueman replacing him.
He did well to parry Gus Scott-Morriss' effort as Oldham pressed forward, before Noah Chilvers volleyed wide while off-balance.
The home side finally made their pressure pay through Kavanagh, who lashed home Chilvers' cross after making space for himself on the right.
Immediately at the other end, Jaden Heskey fired over from the edge of the area as Wednesday searched for a response.
Keillor-Dunn levelled against his former club with 15 minutes remaining, turning inside the box and meeting Max Lowe's cross to set up extra time.
The game became scrappy again, with chances at a premium, but the visitors were passive on the ball and ultimately paid the price.
Sutton headed home from close range after the visitors failed to clear a lofted free-kick, and it proved decisive as Oldham secured their first FA Cup win against Wednesday.