Former Aston Villa forward Gabriel Agbonlahor has claimed that Chelsea striker Romelu Lukaku's value has gone down significantly since he rejoined the side.The Belgian made a sensational £97.5 million return to Stamford Bridge last summer from Inter Milan. However, he has struggled to replicate his best form.He has struck only five goals in 20 Premier League games and also saw a spell on the sidelines, first with a sprain and then with COVID-19.The striker was dealt a fresh injury blow this week after sustaining a knock to his Achilles.talkSPORT@talkSPORT “The £91m they paid for him, I don’t think they’ll get £50m for Lukaku! I think someone could come in for £40m.”🏎 “It’s like buying a Bugatti and you have to give it back…but for half the price!”@Ga11Agbon believes Romelu Lukaku could leave #CFC for as much as £40m. 3:20 AM · Apr 14, 2022455💰 “The £91m they paid for him, I don’t think they’ll get £50m for Lukaku! I think someone could come in for £40m.”🏎 “It’s like buying a Bugatti and you have to give it back…but for half the price!”@Ga11Agbon believes Romelu Lukaku could leave #CFC for as much as £40m. 👀 https://t.co/Ck5aLuJHIgAll this has led many to label him an 'expensive flop.' Questions surrounding his future in London arose following an explosive interview with Sky Italia in January.Agbonlahor has suggested that these issues have contributed to a substantial decrease in Lukaku's market value. Speaking on talkSPORT, he said:“I don’t think they get £50million now for Lukaku. I think someone could come in with a sneaky bid of £40million and Chelsea are in a position where he doesn’t suit the way they play now."Lukaku's form has declined so much that Chelsea manager Thomas Tuchel prefers to start Kai Havertz in the striker's role over him.The Belgian hasn't started a single league game since the start of March before succumbing to another injury that's now set to keep him on the sidelines for a third consecutive match.Chelsea play Crystal Palace at home in the FA Cup semi-finals on Sunday.Chelsea star's future in limboLukaku has remained tight-lipped on his future, but there are rumors that he could be on the move again this summer.PSG have reportedly spoken with the striker's agent over a possible summer move, although it's not clear if the Blues are willing to sell him in the first place.Sky Sports Premier League@SkySportsPLParis Saint Germain are in talks to sign Chelsea striker Romelu Lukaku, according to reports 4:30 AM · Apr 12, 2022114171015Paris Saint Germain are in talks to sign Chelsea striker Romelu Lukaku, according to reports 🚨Former Tottenham Hotspur striker Darren Bent feels the Lilywhites should swoop in for the beleaguered striker if Harry Kane departs north London.Lukaku enjoyed a fantastic relationship with Antonio Conte at Inter. There's a belief that the Italian manager could revive the star's form if they join forces once again.Either way, any deal for him would result in huge losses for the Blues. It all boils down to their manager Tuchel to decide how he fits into his plans going forward.