Arsenal were sent crashing out of the Capital One Cup after a 3-0 defeat at Championship outfit Sheffield Wednesday.
Ross Wallace, Eduardo Lucas Joao and Sam Hutchinson were all on target in a miserable night for the Gunners, who lost two players to injury early on at Hillsborough.
Tuesday's other three games all went to penalties as holders Chelsea crashed out at Stoke, while Championship side Hull beat Leicester and Everton saw off Norwich.
We look at the talking points from a fascinating night's action in the League Cup…
A night to forget for Arsenal
The result may have been far from ideal, but the long-term implications of Arsenal's defeat at Sheffield Wednesday could be more damaging. Alex Oxlade-Chamberlain was taken off with a tight hamstring just five minutes in, then his replacement, Theo Walcott, had to come off 13 minutes later with a calf problem.
At half-time, Paul Merson branded the injuries a "nightmare" for the Gunners, particularly the loss of Walcott: "He's a massive part of this team, and if they're going to go on and win the Premier League he's going to be a big part of it."
With several Arsenal midfielders already on the sidelines, it could prove to have been a costly night for Arsene Wenger's men, with a trip to Bayern Munich and the north London derby both to come in early November.
Youngsters struggle to shine
In naming debutants Alex Iwobi and Glen Kamara in his starting line-up, Wenger has now used more than 200 different players since he took charge at Arsenal.
The Gunners boss has long employed a policy of bringing through younger talent in the cup competitions - Ismael Bennacer and Krystian Bielik were also given their first senior appearances from the bench - but they were humbled by one of the Championship's form teams at Hillsborough.
Sheffield Wednesday hadn't lost in eight games prior to Tuesday night's clash, and they made it difficult for the young Gunners to have an impact on the game, resulting in a damning assessment from Wenger who, after the game, said they "are not ready to play at this level".
Mourinho remains defiant
The Chelsea manager didn't hide after Saturday's dismissal and defeat at West Ham, but he was distinctly expressionless in the dugout. He wasn't giving his under-performing players a chance to hide either, naming a strong line-up for the visit to Stoke, and it was a much-improved display in the opening 20 minutes as Eden Hazard and Diego Costa caused plenty of problems for the hosts.
But then Costa felt the full force of a Charlie Adam challenge and eventually had to come off with a rib injury, and Mourinho's men struggled in the final third without the striker leading the line after the break. Loic Remy sent the tie to extra-time after Jonathan Walters' thunderbolt looked to have sent the Potters through, but the Blues eventually lost on penalties, tasting defeat to Stoke for the fifth time in five League Cup meetings.
The Chelsea boss hasn't been afraid to single out players for poor performances, this season and before, but it was a different tone from Mourinho after the game as he defended his players fervently, saying they should not be criticised for what he felt was a good display: "What some people write and say is really bad for the players; my players tried everything."
Penalty drama still captivates
Three of Tuesday's four games finished 1-1 after extra time, resulting in the equally loved and hated battle from 12 yards. Everton's clash with Norwich at Goodison Park saw Sebastian Bassong and Leon Osman score for either side in normal time, and it was fitting that an open and entertaining encounter would finish with the drama of a shoot-out.
It started well for both sides, but Wes Hoolahan - who impressed throughout the night - slipped in his run-up and Joel Robles kept his effort out, before Nathan Redmond then missed to hand Everton a spot in the last eight.
Eden Hazard, meanwhile, was denied in the last kick of the shoot-out at the Britannia by a fine stop from Jack Butland, compounding Chelsea's misery. At the KC Stadium it was the first penalty that proved decisive, as Hull goalkeeper Eldin Jakupovic tipped Riyad Mahrez's shot on to the upright before the remaining nine spot kicks were dispatched, with David Meyler completing a fine victory for the Championship side over Leicester.
A new style for Leicester?
In the 10 Premier League games involving Leicester so far this season, there have been 37 goals - good entertainment value from Claudio Ranieri's men. But they have been leaky at the back, shipping 17 goals, with only five top-flight sides boasting a worse defensive record.
A much-changed Foxes line-up produced a different kind of display at Hull, sitting back against an in-form side while occasionally trying their luck on the counter.
The problem for Ranieri's men was a lack of threat up front, and although they broke the deadlock in extra time, a mistake from Mark Schwarzer at the other end eventually proved their downfall as they quickly shipped an equaliser before losing the shoot-out.