Southampton have reportedly sent scouts to Portugal to assess high-profile players in games involving Porto and Benfica.
Ralph Hasenhuttl made seven signings over the summer, including full-backs Valentino Livramento and Romain Perraud as well as striker Adam Armstrong, however the Danish boss is said to still be keen to improve his squad in certain areas.
According to The Independent journalist Melissa Reddy, via saintsmarching.com, Southampton were one of several teams to have scouts monitoring players during Benfica's 3-0 victory over Barcelona in the Champions League last month.
The report also states that club representatives were in the stands to watch Porto's Primeira Liga win against Pacos de Ferreira last weekend.
The identity of the players targeted by Southampton currently remains unknown, though it seems they are one of a number of clubs who have discovered the Portuguese market as a place to find potential stars for the future.
Benfica's Darwin Nunez and Porto's Luis Diaz are two Primeira Liga players who have been linked with transfers elsewhere, though it is unlikely that the Saints would be targeting the duo, who are seemingly keen to continue playing in European competition.