Lukaku last week joined the Blues for a club record £28million fee.
"After doing it for West Brom he came here with a lot more pressure but it's been a marriage made in heaven.
"He's obviously cost big money but that's what you have to pay for these premium guys who can put the ball in the back of the net."
The former Blues striker added: "It's a great piece of business by Roberto Martinez and Bill Kenwright. They can have great pride in landing their number one target.
"Rom's certainly a marquee signing. He's young but proven. Only two players have scored more goals in the Premier League over the past couple of seasons."
For the big stories and the banter follow us on Twitter: @tribalfootball