3. Kepa Arrizabalaga (Athletic Bilbao -> Chelsea)
Soon after Courtois made his decision to leave Chelsea, the Blues were desperately in search of a replacement. In meanwhile, Chelsea were failing to find so, and as a result, they had to keep Courtois till then.
But when Thibaut Courtois forced a move to Real Madrid, the Premier League side had no other option, but to trigger the release clause of Athletic Bilbao’s, Kepa Arrizabalaga at the 2018 summer transfer window.
The deal cost them £71.6m, and it made Kepa the most expensive goalkeeper in the history of football.