Antonio Conte has been warned about selling Nemanja Matic (Picture: Getty)

Chelsea would be taking a big risk and losing a crucial player by allowing Nemanja Matic a £40million transfer to rivals Manchester United, according to Mario Melchiot.

The former Blues defender believes Matic played a big role in Chelsea’s Premier League title triumph last season, and thinks he’ll significantly strengthen Jose Mourinho’s side in an important part of the pitch.

United are widely expected to complete a deal for the Serbia international, despite him reportedly being only their third choice midfield target, with Tiemoue Bakayoko looking set to replace him at Stamford Bridge.

Melchiot hopes Antonio Conte knows what he’s doing with the move, as the Dutchman believes Matic cannot be sold without a suitable replacement coming in.

Matic was a key part of Chelsea’s title-winning side last season (Picture: Getty)
Matic looks set to be reunited with Jose Mourinho (Pictures: Getty)

‘He was very crucial in some games Chelsea played last season and I think he did extremely well, even if he wasn’t starting every game,’ Melchiot told talkSPORT.

‘There was a good balance in the midfield, sometimes with him or (Cesc) Fabregas next to (N’Golo) Kante.

‘If he (Conte) makes the choice to let him go to Man United, he better have good backing because, if not, it might come back and bite you later.’

And while Mourinho and Matic didn’t seem to see eye to eye toward the end of the Portuguese’s spell with Chelsea, Melchiot believes he could particularly benefit from working with a midfielder of his quality.

‘You don’t want to make your rivals stronger, especially in the midfield where Jose Mourinho is always focused on having a strong midfield,’ he explained.

Chelsea have regretted a number of player sales in recent years, with Juan Mata another whose shone since leaving them for United, while Daniel Sturridge, Romelu Lukaku and Kevin De Bruyne have also shone at rival Premier League clubs since leaving the Bridge.

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