Bryan Robson believes Manchester United's next move after securing the future of Ole Gunnar Solskjaer must be to bring in a centre-back of the ilk of Virgil van Dijk.
Solskjaer was confirmed as United's permanent manager on a three-year contract on Thursday, having excelled since returning to Old Trafford in place of Jose Mourinho, winning 10 of 13 Premier League games and reaching the Champions League quarter-finals.
Former United skipper Robson is in support of the appointment and he hopes there will be funds available to back Solskjaer in the transfer market.
Having seen rivals Liverpool reach a Champions League final and challenge for the league title since signing Van Dijk in January 2018, Robson believes the recruitment of a commanding centre-half could similarly improve United's fortunes.
"It could take millions in compensation [to get a new manager] and another two years," Robson wrote in the Daily Mail. "We've already been playing catch-up to Manchester City and Liverpool for too long.
"Ole has earned his chance and United would be better off spending any millions earmarked for compensation on world-class players to strengthen his hand.
"I know he has indicated he doesn't need a new centre-back, but that's where I'd disagree. Sure, Ole has improved the defending, but we've seen the impact Virgil van Dijk has had on Liverpool this season.
"A signing of that magnitude, a commanding leader could catapult United forward. You can see the confidence Van Dijk brings to Liverpool's goalkeeper Alisson, his fellow defenders and midfielders.
"That's the type of player United need to sign. A strong summer of recruitment could be the making of Ole's legacy — not necessarily players in quantity, but world-class quality."