Liverpool and Manchester United had scouts posted to see Porto in action this week.

O Jogo says Liverpool raided Porto for Luis Diaz in January and were back watching the Portuguese side on another scouting mission this week.

The Reds sent scouts to the Estadio do Pragao for Wednesday night's Europa League clash.

Porto were undone by Lyon, who now hold an advantage ahead of the return leg, which meant few of their current stars were able to impress.

The Portugal outfit have long been an impressive breeding ground for players, especially those from South America.

Clubs have captured the likes of Radamel Falcao and James Rodriguez from Porto and Liverpool are exercising the possibility of doing so again.

Manchester United also had representatives in the stands as they kept their eye on any possible targets whilst German giants Bayern Munich also had onlookers present.

Midfielder Vitinha was a bright spark on the night as the hosts were beaten. P