Ole Gunnar Solskjaer says it would be "miraculous" if Manchester United are challenging for the Premier League title next season.
It has been a dismal campaign for a side that finished runners-up to Manchester City last term.
A struggling United were initially rejuvenated when Solskjaer replaced Jose Mourinho in December, winning 14 of his first 17 fixtures, but they have stuttered since.
United - irrespective of tomorrow's result against Cardiff - will miss out on a top-four finish and Solskjaer knows his side have to catch up on their rivals.
The Norwegian, whose side are 29 points behind leaders City, said: "Challenging for the title next year would be a miraculous season because we are so far behind at the moment, points-wise.
"It's not like when I used to play that it was us or Arsenal that would win the league, and then Chelsea came.
"Now it's a very competitive competition and we're challenging against the best teams in the world. That tells us that it's going to be a great challenge. We want to get back to where we used to be.
"Next season, we've got to close that gap. If we manage to get to March and be close then that's fantastic."
Mike Phelan is to remain Solskjaer's assistant after signing a three-year contract.
The United manager said: "He's fantastic at his job as assistant manager so I'm very pleased it's been agreed."
Solskjaer is set to overhaul his squad this summer, though he was coy when asked if the Cardiff game would be a farewell for some players.
He said: "It might be your last game but it might be the start of some careers as well. We had some young players knocking on the door all season and we'll start with one or two of the kids as well.''
One player linked with United is Swansea winger Daniel James (21).
But Solskjaer insisted: "I can't comment on every individual. I don't talk about players, even if I wasn't or was interested."