Answer
The record was claimed by Tanguy Ndombélé, a French midfielder, who joined Tottenham Hotspur from Lyon for a fee reported to be around £55 million in the summer of 2019, surpassing the previous record held by Alexis Sánchez's £42.5 million move to Arsenal back in the summer of 2014. Ndombélé's transfer made him the club's most expensive signing, demonstrating Tottenham's commitment to strengthening their squad.