The Atletico Madrid forward was the subject of a £21million offer from the Reds in the summer, but opted to stay in Spain and has been in fine form since.
The 25-year-old has banged 12 goals in the opening 10 games of the season, which has seen his price tag sore.
And now it appears Chelsea are willing to match the £32million release clause in the forward’s contract, in the hope of bringing the Brazilian to the Premier League.
Liverpool had previously lined up the forward as a replacement for Luis Suarez, who they felt was ready to quit the Premier League, but now the Uruguayan has stayed put it appears Chelsea are in pole position.
Mourinho is desperate to bring in a new centre forward, with Fernando Torres, Samuel Eto’o and Demba Ba failing to find the net regularly in the Premier League.
A move in January remains unlikely however, considering Costa only signed his new deal at Atletico in the summer, and any move would see him cup tied for the Champions League.
Could Diego Costa be the right man for Chelsea?
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