Leicester City are reportedly tracking Benfica duo Andre Almeida and Rafa Silva.
According to Portuguese source O Jogo, the Foxes, who were linked with the pair in the January transfer window, sent scouts to Benfica's latest fixture with Boavista last weekend.
The source adds that Leicester, who had a £5m bid rejected for Almeida last month, will have to pay at least £15m to secure the right-back's signature this time round.
Winger Silva, who also played a part in Benfica's 4-0 win at the weekend, has failed to impress in the Portuguese capital since switching from Braga.
Leicester's next outing is a Premier League tie with Stoke City on Saturday.