The Blues re-signed Lukaku, having already signed him in 2011 before selling him to Everton, for a mammoth fee of around £97m.
The London club were desperate to find a lethal striker after last season, when midfielder Jorginho was their top scorer in the Premier League with seven goals.
Lukaku initially wanted to stay at Inter, but realised that Chelsea were serious about bringing him back to Stamford Bridge only after their third proposal.
“I only realised that Chelsea were serious when they made their third offer”, he told Belgian daily Het Laatste Nieuws.
“First they offered €100m.
“Then €105m, €105m plus [Marcus] Alonso.
“Then they offered €110m plus [Davide] Zappacosta, but Inter said no.”
The star striker insisted that he did not want to go behind Inter’s back and talk with Chelsea as they were the club who got him out of a fix at Manchester United.
He met Inter coach Simone Inzaghi, telling him of his desire to join Blues as he no longer felt compelled to play for the Serie A side.
“I didn’t want to go behind Inter’s back”, added Lukaku.
“They got me out of the s***t.
“I was in a deep hole at Man United.
“After training I went to Inzaghi’s office.
“I didn’t want to ruin the atmosphere because I was no longer with my head in Milan.
“So I asked him: please find an agreement.”
While his first spell at Chelsea only saw him make 15 appearances in total for the Blues, he now returns to Stamford Bridge having cultivated the image of a strong striker and he got off to a good start to life in London by scoring on his second debut.
