Eden Hazard takes Chelsea to the highest level and his link-up play with Alvaro Morata makes them dangerous, according to club icon Frank Lampard.
Since signing from Real Madrid in a deal that could reportedly cost as much as £70 million, Morata has scored eight goals and supplied three assists in 15 appearances in all competitions.
The striker has been partnered up top by Hazard in recent weeks, with head coach Antonio Conte adding an extra body into the centre of midfield.
Lampard, Chelsea's record goalscorer, is excited by the way the two work together and believes there is even more to come from the Belgian in particular.
"For me Eden Hazard is the key player for Chelsea," he told Omnisport, speaking thanks to Chelsea FC club partners Yokohama Tyres.
"I think when Eden Hazard is on form and playing well, he's the extra quality that takes Chelsea to the top.
"He did it last season, he did it two seasons before when Chelsea won the league.
"I think he's improving and he's in his prime, and particularly the link between Hazard and [Alvaro] Morata, when they're playing close together and at the top of their game, makes Chelsea a very dangerous team."