Manchester City are keen on signing Porto midfielder Nico Gonzalez.

Sources in Portugal say City have already had a bid turned down for the 23-year-old former Barcelona player.

Reports suggest the bid was about 50m euros (£42m).

City have already signed three players during the current transfer window - Egypt forward Omar Marmoush, Brazilian defender Vitor Reis and Uzbekistan defender Abdukodir Khusanov, at a total cost of over £120m.

Manager Pep Guardiola was non-committal on Friday when asked if he would make further additions.

Guardiola has been concerned about his midfield since Ballon d'Or winner Rodri suffered a major knee injury in September.

The problem has been compounded by injuries to his defenders that have prevented him from using Manuel Akanji or John Stones as alternatives.