© Getty Images Enlarge Koke is reported to have a £17 million release clause in his Atletico contract

Manchester United boss David Moyes has scouted Atletico Madrid's Koke as he continues his search for a central midfielder.

Moyes' attendance at Atletico's 2-0 final Champions League group game victory over Porto on Wednesday night led to fevered speculation in Spain that the Premier League champions were planning a £17 million bid for the 21-year-old.

However Koke has said he is unaware of any interest from United and happy where he is at the moment.

The Atletico youth graduate has been a revelation this season, cementing his place as a key member of a side who easily won their Champions League group and are currently joint top of the Primera Division standings, while also featuring in all seven of Spain's qualifying and friendly games since making his senior debut in August.

Moyes was caught by Spanish TV cameras in a seat in the Vicente Calderon's executive area and, after completing the 90 minutes against Porto in a deeper role than usual, Koke himself told Canal Plus that he was unaware of and unmoved by any potential interest from the English giants.

"I did not know anything about it," Koke said. "Neither does it bother me. I signed a new contract last summer."

That deal runs until 2018, but contains a release clause of just €20 million, a figure which looks more and more of a bargain with each passing week.

Atletico sporting director Jose Luis Caminero played down the visit, saying it was most likely the United boss was running the rule over a potential opponent for later in the competition.

"I suppose that David Moyes has come to see a Champions League team like us," Caminero said. "They have qualified for the last 16. We have spoken, but he did not tell me exactly why he was here."

Koke is the latest in a long list of players Moyes and his coaching staff have watched as United, who endured a frustrating summer in the transfer market, consider signing in their bid to bolster their squad.

Assistant manager Steve Round and first-team coach Jimmy Lumsden went to scout Borussia Dortmund winger Marco Reus when the Champions League finalists beat Napoli last month. Phil Neville, another of United's first-team coaches, has paid a trip to Madrid to watch Real's Sami Khedira, for whom the club bid in the summer, but who is now injured. United are also believed to have checked out Roma midfielders Miralem Pjanic and Kevin Strootman. However, Moyes is known for attending as many games as he can and scouting players assiduously before making offers for them.

United also failed in a bid for Ander Herrera last summer and the Athletic Bilbao player has spoken recently about how he is happy now at his hometown club, and not expecting any repeat of last summer's transfer shenanigans, when lawyers apparently trying to pay his £31 million release clause on United's behalf were claimed to be impostors.

Download ESPN's new UK sport app, a fresh and powerful new way to follow your favourite UK sports news, scores and video.

© ESPN Sports Media Ltd