Manchester City technical director Mike Rigg has hinted the club are keen on Benfica stars Angel Di Maria and Oscar Cardozo.
The South American pair have been strongly linked with big-money transfers in the summer, with City rumoured to be in the chase for both of them.
Blues boss Roberto Mancini was at Anfield during Benfica's Europa League tie with Liverpool and it is believed he was impressed by the duo.
Rigg has now hailed the quality of Cardozo and Di Maria, admitting that the club will keep an eye on them.
Interest"Di Maria and Cardozo are two excellent players, very strong in their respective positions, and hence highly-rated in the international market," he told Record.
"It is logical, there is no need to hide, that a club like Manchester City have to be attentive to players with such potential, who catch the interest of several clubs worldwide.
"I observe many players and I am well documented on these and also other athletes who play in Portugal, but I acknowledge that Di Maria and Cardozo are two fantastic players."
Di Maria, who signed for Benfica from Rosario Central in 2007 for €8million, has been included in Argentina national coach Diego Maradona's provisional list for the World Cup.
Cardozo, who netted three times against Liverpool in the Europa League, is the club's top scorer, with 33 goals in all competitions this season.