Frank Lampard believes if Chelsea tie Antonio Conte down to a new contract it would be their signing of the summer.
Conte has signalled his eagerness to stay next season but an extension to his current deal, which expires in 2019, is yet to be confirmed.
The Italian is one of the most sought-after coaches in Europe after leading Chelsea to the Premier League title in his opening season at Stamford Bridge.
And while the Blues are set to make a number of big-money signings this summer, Lampard, who scored 211 goals in 649 appearances for the club, says Conte would be the best.
“Antonio would be their most important signing – for me he was their man of the season,” Lampard said.
“You talk about player of the year, I’m all for giving the players credit but because it was such a dramatic uplift from the year before I think you have to give him huge credit.
“You saw the system change and how he made them play in that formation, it worked well.
“I think he’s a huge signing for them. I have no doubts, I don’t know but I’m pretty confident he’ll be there and they’ll bring in players to play in the system he wants to play.”
One man who looks likely to leave Chelsea is Diego Costa, with Conte making clear to the Spain international he is no longer in his plans.
Romelu Lukaku is high on the list of potential replacements after the Belgian scored 25 league goals for Everton last season.
Lukaku joined Chelsea as an 18-year-old in 2011 but was given limited chances in the first team and eventually moved to Merseyside three years later.
“Chelsea bought that player as a youngster and maybe it was too early or whether he didn’t get the chances I don’t know,” Lampard said.
“But I love his attitude, the way he plays and very determined. I remember training with him and he was always practising and he wanted to score goals. I respect lads like that.
“He deserves the best and if Costa does move on and they want to get something like for like in the style of a big front man who score goals then Lukaku has proved he can do that.”