João Félix — Atlético Madrid to Chelsea (2023) — €45M (loan → permanent)

João Félix’s €127 million move from Benfica to Atlético Madrid in 2019 was the fourth most expensive transfer at the time, but his €45 million loan-to-permanent transfer to Chelsea in 2023 highlights a dramatic fall from that peak. At Atlético, he scored 45 goals in 131 games—a respectable but underwhelming return compared to expectations, especially given he is 30% less productive than the average for a €100m+ attacker. His struggles under Diego Simeone’s defensive system illustrate a classic mismatch of talent and tactics, wasting generational potential as he averaged only 13 goals per season in La Liga.