The futures of Paul Pogba and David de Gea are a concern for Manchester United, says Gary Neville, with the Red Devils needing big money to be spent and two years in which to become title challengers.
Questions continue to be asked of key man at Old Trafford, with transfer speculation being sparked amid hints at interest from elsewhere and contracts running down.
World Cup winner Pogba is said to be on the transfer radar of fellow Frenchman Zinedine Zidane at Real Madrid, while first-choice goalkeeper De Gea and England international forward Marcus Rashford are among those yet to commit to fresh terms.
Neville sees that as a worry, with Ole Gunnar Solskjaer needing to build around star turns as he prepares to undertake a rebuilding project at the Theatre of Dreams.
Former United defender Neville told Sky Sports of what needs to be done by the Red Devils in upcoming transfer windows: "He [Solskjaer] needs big money unless they can cash in on someone who is worth big money - there's David de Gea and Paul Pogba, who is reportedly being courted by Real Madrid.
"The two I'd be worried about are De Gea and Marcus Rashford. There's talk about both of them not signing a new deal but I think Rashford will sign, that's not in doubt.
"They will have to throw money at it. However, it's not as bad as everyone makes out.
"Ole Gunnar Solskjaer's job is to coach the team. He identifies which players he wants and the club gets the maximum value for the players going out and they bring in the right players.
"It's a turf war out there: agents, recruitment guys, consultants and clubs like Real Madrid are looking to rebuild and invest heavily. To get four or five players that you want and get the four or five you want out is a big, big job.
"My concern is for Ole is: who is going to do this for him?
"That person might be there already but it's a bit of an abyss in terms of the recruitment side of things.
"I don't know who at the club could navigate the job that needs to be done to put Manchester United into championship territory. It's a two-year job to turn that squad into one that can win the title. I don't think they'll get everyone in they want and I don't think they'll get the ones out - it will take two years and plenty of patience."
Among those being linked with moves away from Manchester are Alexis Sanchez, Juan Mata and Ander Herrera, with the former having struggled to live up to expectations while two Spanish midfielders are heading towards free agency.