Manchester United are set to make an enquiry about the availability of Benfica striker Goncalo Ramos ahead of the January window although manager Erik ten Hag has been told it is not certain a striker will arrive next month, sources have told ESPN.

United are looking to add a forward in the January window following the departure of Cristiano Ronaldo.

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Ramos is among a number of players being followed including Cody Gakpo, Rafael Leao and Joao Felix, although there remains a view at Old Trafford that January is not the ideal time to bring in new players.

Sources have also told ESPN that there are significant budget constraints as a result of the COVID-19 pandemic and a higher than expected outlay on transfers last summer.

Ten Hag, however, believes the squad is short of firepower following Ronaldo's exit and would like the club to explore whatever options are available.

Ramos came close to leaving Benfica last summer but stayed after the Portuguese side came through qualifying to book their place in the Champions League group stages.

Benfica were considering bids of around €20 million before the start of the season but Ramos' stock has risen considerably after he scored a hat trick for Portugal in their World Cup round-of-16 tie against Switzerland. He has scored 14 in 21 games for Benfica so far this season.

Meanwhile, Gakpo's valuation has almost doubled after his impressive form in Qatar.

United were quoted around €30m by PSV Eindhoven in the summer but after three goals for the Netherlands at the World Cup, it is now closer to €50m. Sources have also told ESPN that PSV are keen to keep Gakpo in January to help their bid to win a first Eredivisie title since 2018.

Sources have told ESPN that United have been alerted to Felix's availability in January, although Atletico Madrid's valuation of around €100m is problematic.

One option being considered is presenting Atletico with a loan offer in January with an obligation to make the move permanent at the end of the season. Felix's Atletico teammate, Alvaro Morata, is also of interest after enquiries were first made in the summer.