Diego Costa will go from Atlético Madrid to Chelsea on a £32 million transfer.
Negotiations have been ongoing over the past two months.
Costa has told teammates he will be leaving this summer.
"I feel good at Atlético, I am happy in Madrid," said Costa this weekend. "We will see what happens. There are offers, but it is too early yet to talk. Now I am just thinking about the end of the season, I want to win the Champions League and La Liga."