Aston Villa manager Roberto Di Matteo has begun his tenure at the club with back-to-back defeats as his side have crashed out of the EFL Cup following a 3-1 reverse at League Two outfit Luton Town.
The Championship newcomers took the lead through Jordan Ayew in the 13th minute and looked in control until the Hatters equalised with their first shot on target in the 35th minute.
Jake Gray netted Luton's leveller and things got even better for the underdogs in the 53rd minute when Cameron McGeehan doubled their lead. An own goal by Jores Okore put the result beyond doubt and compounded the Villans' misery.
All three of the evening's other matches went to extra time, with Burton Albion booking their place in round two with a 3-2 win over Bury following a 1-1 draw after 90 minutes, Stuart Beavon and Callum Butcher netting decisive goals before Niall Maher bagged a consolation for Gary Flitcroft's side.
Leeds United narrowly avoided an upset at League One Fleetwood Town, who took the lead in the 13th minute through Aaron Holloway before Marcus Antonsson forced extra time with an equaliser in the 89th minute.
There was more drama after 90 minutes as Gary Monk's men went ahead in the 94th minute through Chris Wood's penalty kick, before a strike from Fleetwood's Ashley Hunter took the game to extra time.
Eggert Jonsson missed the decisive kick for the League One side, sending his team crashing out 5-4 on penalties.
Queens Park Rangers also needed a penalty shootout to see off Swindon Town, with the two teams tied 2-2 after 120 minutes at Loftus Road.
The Hoops booked their place in the next round after Anton Rodgers and Bradley Barry missed from 12 yards, with the hosts triumphing 4-2 in the shootout.
Results in full: Burton Albion 3-2 Bury, Fleetwood Town 2-2 Leeds (Leeds win 5-4 on pens), Luton 3-1 Aston Villa, QPR 2-2 Swindon (QPR win 4-2 on pens)