Tottenham Hotspur suffered their second defeat in English knockout football in a matter of days as they lost 2-0 to Crystal Palace in the fourth round of the FA Cup on Sunday.
Connor Wickham gave the unfancied Eagles, 29 points adrift of Spurs in the Premier League, a ninth-minute lead before a penalty by former Tottenham winger Andros Townsend made it 2-0.
Spurs' Kieran Trippier missed with a penalty before half-time as Tottenham suffered more spot-kick woe following Thursday's shoot-out defeat by Chelsea, another of their London rivals, in a League Cup semi-final.
FA Cup-holders Chelsea had no such problems later on Sunday as they marked striker Gonzalo Higuain's club debut with a 3-0 win at home to Championship side Sheffield Wednesday.
Willian scored twice either side of a goal from highly-rated English teenager Callum Hudson-Odoi, linked with a transfer window move to German giants Bayern Munich.
Chelsea did not have things all their own way against second-tier Wednesday, who thought they had been awarded a penalty in the 22nd minute.
Joey Pelupessy tried to meet Steven Fletcher's pass, with Ethan Ampadu sliding in to win the ball before being kicked by the Wednesday midfielder.
Referee Andre Marriner awarded a penalty but this was overturned by VAR, being trialled in some English cup fixtures this season.
"It's crazy," said Owls' caretaker boss Steve Agnew, holding the fort ahead of Steve Bruce's imminent arrival.
"Obviously the VAR decisions are correct but what baffled me was surely it's a corner if it came off their player. The referee gave a drop ball. And a minute later they have a penalty."
Wednesday's woe was compounded soon afterwards when Willian scored from the spot after Sam Hutchinson trod on Cesar Azpilicueta inside the box.
VAR was called into action again but this time Marriner's decision was upheld and Willian, after appearing to offer the spot-kick to Higuain, made no mistake.
Chelsea had to wait until midway through the second half for Hudson-Odoi to make it 2-0 before Willian, playing a neat one-two with Olivier Giroud, completed the scoring seven minutes from time.