Joseph Anang was the hero with two shootout saves as League Two Stevenage defeated local rivals Luton 3-0 on penalties to progress to the second round of the EFL Cup following a 2-2 draw in normal time.
The home side conceded the lead twice in a chaotic four-goal first half, with goals by Elliott List and Ben Coker cancelled out by Luton's Cameron Jerome and Admiral Muskwe.
A goalless second half led to penalties, in which Championship outfit Luton failed to score.
Despite the two-league gap between the sides it was an even affair from the off, aided by the fact Hatters manager Nathan Jones made 10 changes to the side that started their win against Peterborough at the weekend.
Both sides scored within the first five minutes of the game, with Stevenage going ahead through last season's top scorer List in the second minute, only for Luton debutant Jerome to draw the visitors level three minutes later.
Pressure from Stevenage was rewarded in the 26th minute when Coker curled in a free-kick from the edge of the Luton box.
Boro again failed to hold onto their lead, though, as former Leicester man Muskwe struck for the visitors five minutes before half-time.
Neither side was able to dominate a calmer second half, but Stevenage and Anang held their nerve in the shootout to progress to the next round.