LONDON (AFP) - Eden Hazard squandered the decisive penalty as Stoke City deepened Chelsea manager Jose Mourinho's woes with victory in the League Cup on Tuesday, while second-tier Sheffield Wednesday stunned Arsenal 3-0.
After Jon Walters put Stoke ahead with a fine 20-yard shot at the Britannia Stadium,, Chelsea substitute Loic Remy, on for the injured Diego Costa, lashed home an injury-time equaliser to make the score 1-1.
Following a goalless period of extra time, the first nine penalties of the shootout were all scored, only for the out-of-form Hazard to see his 10th spot-kick parried by Stoke goalkeeper Jack Butland.
The Belgian's mishap condemned Mourinho's side to their ninth defeat in all competitions this season and saw the holders exit the tournament in the fourth round.
It came hot on the heels of a 2-1 defeat at West Ham United on Saturday, which left Mourinho facing a Football Association misconduct charge after being sent to the stands, and ramped up the pressure on the Portuguese ahead of Saturday's Premier League home game with Liverpool.
With Chelsea currently 15th in the league table and third in their Champions League group, British newspapers have speculated that Mourinho could be sacked if their fortunes do not improve quickly.
At Hillsborough, Arsene Wenger's Arsenal were well beaten by Championship side Wednesday and also lost Alex Oxlade-Chamberlain and Theo Walcott to injury in the first half.
Ross Wallace put Wednesday ahead after 27 minutes and then teed up Lucas Joao for the hosts' second goal shortly before half-time, with Sam Hutchinson completing victory early in the second period.
Asked how his young fringe players had handled the occasion, Wenger delivered a scathing assessment, telling Sky Sports: "It was too high for them. They are not ready to play at this level, none of them."
On the injuries his team suffered, he added: "We are short now because we lose Chamberlain today, we lose Walcott and we have already a few injuries.
"It is a big blow for us, of course to lose the game, but even more for the other competitions, which are very important for us, to lose two players of that stature." It was Wednesday's second Premier League scalp in this season's competition, following their third-round win at Newcastle United, and brought Arsenal's run of four successive victories to an end.
Wenger made eight changes to the team that beat Everton 2-1 on Saturday for the trip to Hillsborough, which was a repeat of the 1993 final.
Oxlade-Chamberlain was one of only three players who kept their places, along with Petr Cech and Olivier Giroud, but he went off in the fifth minute after pulling up while running along the touchline.
Walcott replaced his England team-mate, but he in turn was forced off 13 minutes later with an apparent calf injury.
Ismael Bennacer, a 17-year-old midfielder, came on, joining Glen Kamara and Alex Iwobi in making his Arsenal debut.
Wednesday took the lead nine minutes later when a neat move down their left flank culminated in Daniel Pudil cutting the ball back for Wallace to steer a first-time shot inside the left-hand post.
Wallace teed up Wednesday's goal in the 40th minute after a short corner, swinging over a cross from the left for striker Joao to head home.
Wednesday completed victory six minutes into the second half when Barry Bannan's free-kick found Tom Lees in acres of space at the back post and he volleyed across goal for Hutchinson to score with his knees.