Both Watford and Crystal Palace had officials watch Friday night’s match between FC Porto and Tondela, reports A Bola.

The Portuguese champions, playing the match at home, won the game 1-0 but it wasn’t one of their most spectacular performances of recent times.

In the stands were scouts from numerous clubs, including Watford and Palace.

Tottenham and Manchester United were also there, along with Saint Etienne, Lens Toulouse, Montpellier, Marseille, Cetla Vigo, Deportivo la Coruna, Eibar, Eintracht Frankfurt, Borussia Dortmund and AC Milan.

For Watford, it wouldn’t be too hard to conclude the target may be Hector Herrera. The Mexican midfielder was linked with the Hornets in 2017 and it’s popped up on occasion since.

Herrera’s contract ends in June and the 28 year old is being linked to a never ending string of clubs, which is only going to be further encouraged by the number of scouts watching Porto at the moment.

Given the nature of any potential deal, either cut price in January or free in the summer, it’s a reasonable bet he’s one of the ones being watched.