On top of his transfer troubles, Mourinho had a host of injuries and players lacking match sharpness after the World Cup to contend with.
Mourinho was particularly annoyed to miss out on a series of centre-back targets, including Leicester's Harry Maguire who shone for England in Russian Federation.
Mourinho warned it could be a "difficult season" if United did not bring in at least one more face, with centre-back the main focus in a market that was inflated by last summer's deals.
As I was saying on BBC Radio 5 live on Friday, United have a very strong squad.
"We play against a team that invest more than us".
Given the pressure on him at times over the last few seasons, with questions of his physical condition and mentality, Shaw will be delighted to have scored.
Luke made one mistake - towards the end of the game when he was caught in possession inside his own area by Vardy - but he will not need to be told about it.
Having had a full pre-season behind him, undisturbed by the World Cup, Alexis Sanchez should have come into this game like a house on fire.
"Pogba was a monster", said Mourinho.
I won't be full from a World Cup. "We will have the same players, the injured players are not going to be back", said Mourinho. "We have Paul with nine days training, Rashford with 11 days training, Fellaini with nine days training and of course we will be in a better condition, I don't remember in my career to be so much in trouble to make changes, because I want to make five or six [substitutions] and I have only three". "I haven't won the Premier League, I haven't won the Champions League, I haven't won the European Championship so there are more to win", he said.
Gave the penalty away to put Leicester 1-0 down early on with a ridiculous handball, booked in the second half before finally being substituted on 63 minutes, this was definitely a night to forget for Daniel Amartey.
Leicester manager Claude Puel felt his side deserved a draw. I am happy with the squad and the transfer window. "We showed good control, good football, a lot of chances".
"It was tough for Harry Maguire, he gave his best and had a good game".