Blackburn produced a remarkable turnaround with two stoppage-time goals to beat Oldham 3-2 in the Carabao Cup first round.
Mohamed Maouche's 20-yard effort looked to have won it for the League Two strugglers 10 minutes from time but their hearts were broken twice in the six minutes of added time, as Stewart Downing's first for the club levelled matters before Joe Rothwell's tap-in spared Blackburn's blushes.
Rovers dominated early on but Nepomuceno sucker-punched them with a superb 20-yard strike into the bottom corner.
Dack scored his first of the season in the 70th minute, capitalising on a defensive mistake to lash home, before Latics regained the lead 10 minutes later as a Joe Grayson clearance fell straight to Maouche, who emphatically found the top corner.
All looked lost for the home side, especially when Dack shot wide with minutes remaining.
But Downing equalised with a precise 25-yard strike in the 92nd minute and, with the wind in their sails, Rovers grabbed a dramatic winner three minutes later when Dack ran onto Danny Graham's flick and squared for Rothwell to tap in.