Chelsea will pay £30million to sign Nicolas Jackson from Villarreal with final talks ongoing over the exact structure of the deal.
The 21-year-old will join for a fee almost identical to his release clause with just the payment method being discussed.
Jackson began talks with Chelsea last week, as first revealed by Standard Sport, and has since fully agreed personal terms.
Jackson has been on holiday in Portugal and Ibiza ahead of the transfer but is soon expected in London to complete his medical.
Chelsea were alerted to Jackson as a potential option after seeing him score nine goals in his last eight LaLiga matches. They have moved quickly to secure his services from under the noses of rivals Aston Villa and AC Milan.
Meanwhile, the Blues are understood to be making good progress in negotiations to sign Moises Caicedo from Brighton.
The 21-year-old is keen to move to Stamford Bridge and is ready to agree personal terms but talks over a fee have proven difficult.
Brighton have already rejected a £60m bid from Chelsea for Caicedo and are demanding closer to £100m as discussions continue.
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Seagulls boss Roberto De Zerbi has a verbal agreement with the player to not stand in his way should a suitable offer come in.
Chelsea will also look to sign a goalkeeper as they begin to raise well over £100m through high-profile player sales, including Kai Havertz to Arsenal and Hakim Ziyech, Kalidou Koulibaly and Edouard Mendy to clubs in Saudi Arabia.