Tottenham boss Mauricio Pochettino was at the Wanda Metropolitano on Sunday.
Pochettino took in Atletico Madrid's 1-0 win over Real Betis.
The Argentine, instead of going to the Estadio Mestalla to witness his European rival Barcelona live, preferred to take note of the performance of Diego Simeone's men, perhaps in view of a hypothetical meeting during the latter stages of the competition.
A former player and coach of Espanyol, Pochettino chatted in the director's box at the stadium with Clemente Villaverde before the game, reports Marca.