Chelsea have agreed a £30m deal to sign attacking midfielder Willian from Russian club Anzhi Makhachkala subject to a work permit hearing, reports BBC Sport.
The 25-year-old Brazilian was close to joining Tottenham after having a medical on Wednesday.
But it is understood Chelsea made their move at around 18:00 BST on Thursday, with a fee and personal terms agreed within 24 hours.
Willian will have a medical before his work permit hearing next week.
The transfer was made possible after Blues owner Roman Abramovich, whose fellow Russian oligarch Suleyman Kerimov owns Anzhi, intervened.