For much of the 90 minutes, played in everything from bright sunshine to torrential rain, he watched a reserve XI match one of the Premier League's top teams. In fact, United were only undone by a goal of the season contender from Luke Thomas and a bullet header from Caglar Soyuncu.
Leicester's 2-1 victory was their first top-flight win at Old Trafford since 1998 and handed Brendan Rodgers' side a boost in the race for Champions League football at the expense of Liverpool, who visit here in just over 48 hours. The way James Maddison, Kelechi Iheanacho, and Hamza Choudhury sank to their knees when Craig Pawson blew the final whistle said everything about how tough their evening had been. It was a United team without their star names but one which displayed enough fight and spirit to make up for it.
"We started off slow as you might expect because they have not had any time to prepare for the game, but after they scored, we had nothing to lose," said Solskjaer.
"We played some very good stuff, and I was pleased with it. We have not had too much time to prepare, and we went into half-time pleased but didn't get out of the traps and they got a goal from a corner that should have been a throw."
As soon as the Premier League told United they would have to play three times in five days, Solskjaer hinted he would be forced into a host of changes for Leicester's visit, and he wasn't bluffing. In all, he made 10 from the team which won at Aston Villa on Sunday with only Mason Greenwood keeping his place. Amad Diallo and 19-year-old Swedish forward Anthony Elanga were both handed their first Premier League starts for an XI that still cost more than £200 million, and had the insurance of Bruno Fernandes, Paul Pogba, Marcus Rashford, and Edinson Cavani on the bench.
"It can't be like this again," said Solskjaer, still struggling to hide his anger at the schedule chosen by the Premier League following the postponement of the Liverpool game due to fan protests.
"We can't play like Thursday, Sunday, Tuesday to Thursday, it is impossible that's the reason we made the changes. It's unheard of. It is impossible for the players to perform at this level going from Thursday, Sunday, Tuesday, Thursday." The announcement of United's team an hour before kick-off prompted outrage from some Liverpool fans on social media who insisted Solskjaer had deliberately handed Leicester a boost in the race for the top four. For 45 minutes, they were pleasantly surprised.
The 19-year-old Thomas gave Leicester the lead after 10 minutes with a beautifully-guided volley into the top corner but after Mason Greenwood scored his eighth goal in 11 games to equalise five minutes later, United were the better team.
It was only once the hosts began to tire in the second half that Leicester looked likely to score again and even then, it was from a set piece, Soyuncu getting in between Nemanja Matic and substitute Rashford to score from Marc Albrighton's corner.
It is a vital win for Leicester, who bounced back from a disastrous defeat to Newcastle to move back up to third in the table and, more importantly, extend their lead over fifth-place West Ham to eight points. They need four points from their final two games to be sure of Champions League football next season and also have the FA Cup final at Wembley to look forward to on Saturday.
"It was a huge step [towards the Champions League]," said Rodgers. "I am so proud of the team. We started well and Luke scored an amazing goal.
"Once we scored we went sloppy and gave the ball away too easily which encouraged them. In the second half, we were much better and restricted them.
"The players have definitely overachieved with all the big teams around. Now we can really enjoy the final at the weekend."
With the title race officially over, Solskjaer's immediate task is to secure second place, win the Europa League, and then work out how to bridge the gap with City next season. For the Norwegian, the answer is simple.
"If you want to take up the challenge with them we need to strengthen our squad," he said.
"Congratulations to them. They have had a fantastic season. I am very pleased with my boys that have made it to the last 10 days with a Manchester City side ahead of us that are lauded as the best in Europe. "We want to take the next step and it might be that we need a couple more [signings] to strengthen the squad."