Chelsea scouts have long been watching 17-year-old Anderlecht striker Lukaku, but saw him have no joy when the 6ft 3in 'new Didier Drogba' came up against Lombaerts in the Europa League.
In demand: Nicolas Lombaerts (left) in action for Zenit against Anderlecht earlier this month
While Carlo Ancelotti is short on central defensive options, particularly with injury problems for John Terry and Alex, a move for the 25-year-old would be a surprise.
Lombaerts has been a regular for Zenit since signing from Gent in 2007 and recently signed a new four-year deal with the Russian champions.
Even he is taken aback by the link to Chelsea, saying: 'It's nice to be talked about by such clubs, but it's the first I've heard about it.
'But if Romelu Lukaku is being considered by Chelsea and Real Madrid, then their scouts will have also seen that twice I had him in my pocket.'
The prolific Lukaku has scored 12 in 27 games this season, but drew a blank during two defeats with Anderlecht against Zenit.
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