Manchester United manager Solskjaer saw his side lost 3-0 to Barcelona in the Champions League on Tuesday evening.
It was a torrid night for the Red Devils who, eight years after facing the Catalan giants in the final of Europe’s top-tier competition, were outplayed once again.
Lionel Messi scored twice for Barcelona to put Manchester United to the sword, with Philippe Coutinho hitting a sublime third in injury time.
For Solskjaer and his side, it was another reminder of how far they have fallen behind the European elite.
And the Manchester Evening News say the 46-year-old has been promised a minimum of three signings in the wake of the defeat.
However, that could rise to four if, as expected, Ander Herrera leaves for PSG on a free transfer.
United are likely to sign a centre-back this summer with Kalidou Koulibaly and Raphael Varane among their dream transfer targets.
A right-winger is also in their sights with Jadon Sancho, of Borussia Dortmund, a priority target.
And a new right-back to replace club captain Antonio Valencia is also being eyed.
Solskjaer, meanwhile, hinted at signings for United this summer immediately after the Barcelona game.
“We’re on with the job and have spoken to the players about it as well,” the 46-year-old said.
“That we need to get the best out of each other, create an environment of top, top, top class attitude, world-class attitude every single day.
“Because we’ve got good players and I’ve got good players to work with.
“And, as I said, at the moment we’ve done really, really well to get to the quarters and challenge for top four.
“So we’ve got a rebuilding job but it starts with the coaches and players, and of course one or two additions to the squad will happen in the summer.”
United are next in action against Everton in the Premier League on Sunday (1.30pm).
The Red Devils beat the Merseyside outfit 2-1 earlier in the season.