Frank Lampard has backed Chelsea's pursuit of Romelu Lukaku, insisting his former club need a player with a similar "physical presence" to Diego Costa.

Costa has been told by Antonio Conte, via text message, to find a new club this summer and Standard Sport understands Lukaku is the manager's first-choice to replace him.

Everton have set an astonishing £100million asking price for the Belgium international, who has scored 87 goals after four years at Goodison Park, and Lampard is wary of the "inflated" transfer market.

Chelsea's all-time top scorer feels Costa will be hard to replace but welcomes the interest in a striker who has proven himself in England for many years.

"I think he is a fantastic striker, we've all seen that since he arrived at Chelsea," he told Sky Sports of Diego Costa. "He will be very difficult to replace, there's no doubt about that.

"I don't know where Diego Costa is, where his mind is, whether he wants to leave or not, that's all speculation but one thing is for sure is that you've got a great striker in him so if he stays, brilliant, if he doesn't then you'll have to go to the top end of world strikers to replace him.

"He is an all-round physical presence with the quality to get you goals, that's not easy to find in the modern game. If Chelsea do lose him, they will have to make sure they get the right signing to keep going forward."

Lukaku spent three unhappy seasons at Chelsea from 2011 to 2014, making 10 goalless appearances before being shipped out on successful loan spells at West Brom and then Everton.

​Lampard continued: "I know Lukaku from playing with him. It was early on in his career and he probably didn't get the chances and he's certainly developed to a huge degree since he's left the club.

"I think Lukaku would be a great option and the only thing that Chelsea have to look at is the inflated market that is around now which is very tough and they will take that into account.

"In terms of an all-round striker, proven to have scored goals with Everton last year and the last two or three seasons in the Premier League, he would be an option for them.

The players on Chelsea’s transfer shortlist 16 show all The players on Chelsea’s transfer shortlist 1/16 The players on Chelsea's wishlist... Lindsey Parnaby/AFP/Getty Images 2/16 Alexis Sanchez | Arsenal Arsenal FC via Getty Images 3/16 Alex Sandro | Juventus Getty Images 4/16 Alex Oxlade-Chamberlain | Arsenal Stuart MacFarlane/Arsenal FC via Getty Images 5/16 Ross Barkley | Everton Getty Images 6/16 Djibril Sidibe | AS Monaco AFP/Getty Images 7/16 Virgil van Dijk | Southampton Getty Images 8/16 Adama Traore | Middlesbrough 9/16 Cedric Soares | Southampton Getty Images 10/16 Ryan Bertrand | Southampton Ian Walton/Getty Images 11/16 Mousa Dembele | Celtic Getty Images 12/16 Fernando Llorente | Swansea Getty Images 13/16 Marco Verratti | PSG AFP/Getty Images 14/16 Faouzi Ghoulam | Napoli Francesco Pecoraro/Getty Images 15/16 Danny Drinkwater | Leicester City Getty Images 16/16 Renato Sanches | Bayern Munich Bongarts/Getty Images 1/16 The players on Chelsea's wishlist... Lindsey Parnaby/AFP/Getty Images 2/16 Alexis Sanchez | Arsenal Arsenal FC via Getty Images 3/16 Alex Sandro | Juventus Getty Images 4/16 Alex Oxlade-Chamberlain | Arsenal Stuart MacFarlane/Arsenal FC via Getty Images 5/16 Ross Barkley | Everton Getty Images 6/16 Djibril Sidibe | AS Monaco AFP/Getty Images 7/16 Virgil van Dijk | Southampton Getty Images 8/16 Adama Traore | Middlesbrough 9/16 Cedric Soares | Southampton Getty Images 10/16 Ryan Bertrand | Southampton Ian Walton/Getty Images 11/16 Mousa Dembele | Celtic Getty Images 12/16 Fernando Llorente | Swansea Getty Images 13/16 Marco Verratti | PSG AFP/Getty Images 14/16 Faouzi Ghoulam | Napoli Francesco Pecoraro/Getty Images 15/16 Danny Drinkwater | Leicester City Getty Images 16/16 Renato Sanches | Bayern Munich Bongarts/Getty Images

"But there are others so I wouldn't want to try to second guess where they are looking around. I'm sure they will look at the player in the same type as Diego Costa.

"They need a physical presence, they got a lot of skilfull players behind and will want to find someone who can replicate what Costa did: a physical presence and also give them 20-plus goals a season."