The Blues boss is known to be desperate to land a top-class goalscorer to fire his team to domestic and continental glory after growing frustrated with his current crop of centre-forwards.
He attempted to snap up Manchester United’s Wayne Rooney last year to solve his issues, but now he has shifted his sights to three of European football’s finest marksmen.
Costa is a player ‘The Special One’ has been tracking for some time, with the Brazilian-born ace having been in electric form for some time.
Atletico Madrid are rumoured to be willing to sell their man in the summer for a big money offer, and are holding out for close to his £32m release clause – which will become active in six months’ time.
Cavani is also on Mourinho’s radar amid talks that he is unsettled at PSG.
Chelsea were linked with the prolific Uruguayan ahead of this season, but they were unable to compete with the £50m offer put together by the Ligue 1 champions.
Despite being one of their biggest stars, Cavani is thought to be ready to leave after just a year at the Parc des Princes after playing second fiddle to Zlatan Ibrahimovic.
The final man The Blues are looking at is Mandzukic, who may be looking to leave Bayern Munich with Robert Lewandowski due to arrive in the summer and take his starting role.
Mourinho will only sign one of the three, and is said to have around £40m to do so.