Manchester United have been told by Owen Hargreaves that they need to make at least four additions during the summer transfer window.
The Red Devils are expected to be busy when the next opportunity to recruit presents itself.
Ole Gunnar Solskjaer is working with a side inherited from Jose Mourinho and is yet to put his own stamp on things after resisting the urge to tinker in January.
There have been calls for the Norwegian to be handed big money, with suggestions that United require Champions League football and world-class additions in order to compete for major honours.
Hargreaves shares that opinion, with the former Red Devils midfielder claiming that additions are required down the spine of the side.
He told BT Sport: “I think they need four this summer.
“I think recruitment is going to be so important for Manchester United.
“[They need a] director of football, Ole Gunnar is going to need that help.
“For me, it showed [against Barcelona] they need a defensive midfield player in that position.
“Fred played there, he’s a ball player. In three moments in the game where he could win a challenge or stop someone, he just didn’t do that.
“So I think he’s an eight like [Paul] Pogba, I thought [Scott] McTominay was terrific.
“Centre back, central midfield player is going to be so important, and a right-winger.
“I think they’ve got great potential but the recruitment this summer has to be spot on.”
Solskjaer has already hinted that transfer plans are being pieced together, with another “rebuilding job” about to be undertaken at Old Trafford.
Several big names are said to be in United’s sights, with there likely to be plenty of comings and goings over the next few months as fresh faces are welcomed and deadwood moved on.
Solskjaer has said: “We need to create an environment of top, world-class attitude every single day.
“We’ve got a lot of good players to work with but as I have said, we have a rebuilding job.
“It started with coaches, players and of course one or two additions in the summer.”