Watch: Jose Mourinho furious at 'ridiculous' Manchester United mistakes in loss to Tottenham
Eriksen opened the scoring after 11 seconds, setting Spurs up for a 2-0 win at Wembley.
Jose Mourinho accused his Manchester United players of failing to follow instructions after Christian Eriksen scored just 11 seconds into Tottenham Hotspur's 2-0 win at Wembley.
United manager Mourinho was furious with his side's defending after they made a host of mistakes that allowed Eriksen to blast Tottenham ahead with the joint second fastest goal in Premier League history.
Phil Jones allowed Harry Kane to win a header from the kick-off and, with the rest of the United defence caught flat-footed, Dele Alli pounced with a deft pass that Eriksen steered home from close-range.
Adding insult to injury for Mourinho, Jones booted a Kieran Trippier cross into his own net midway through the first half to double Tottenham's lead.
United's first defeat in nine league games would have been even more painful had the hosts converted more of the numerous chances they created.
Mourinho had no doubt where the blame lay as he criticised his players for failing to follow the warnings he had given about Tottenham's aggressive start to matches.
"I don't think it is very normal to concede a goal like we did after 15 seconds," he said. "It is especially ridiculous because the players, they watch it before, we analyse opponents and work on opponents' dynamics and routines.
"The players they knew the long ball, they knew that Harry Kane - before the kick-off, is already inside the opponent's half. We knew everything.
"Then we don't press the ball - one mistake. We don't pick the ball in the air - second mistake. We don't win the second ball on the ground - third mistake. We don't cover the inside when Eriksen comes - four mistakes. Four mistakes after 15 seconds and you are losing 1-0 against a good team."
United are now 15 points behind City and Mourinho admitted he harbours no hopes of catching Pep Guardiola's side. Instead, he will focus on ensuring United survive the fight to qualify for next season's Uefa Champions League via a top four finish.
"I always think when the leader has a certain distance, I have been there a few times, you are calm, you are relaxed and you don't feel the pressure," he said. "You know that your opponent, sooner or later, is going to drop at least a couple of points and you are completely in control.
"We play match after match, yes the Premier League finishes for us at Old Trafford in May against Watford but you knew the distance to the leader was already considerable even before this match.
"Now we have us, Chelsea, Spurs, Liverpool, Arsenal - we will be there fighting for the positions."
Mourinho also revealed a knee injury forced Marouane Fellaini to be taken off just seven minutes after his second half introduction as a substitute.
"Fellaini came off because he had something in his knee. Unlucky for him and unlucky for me," he said.
Tottenham's win puts them just two points behind fourth placed Chelsea and third placed Liverpool, with a crucial trip to Anfield looming on Sunday.
Updated: February 1, 2018 10:32 AM