Arsenal, Newcastle United, Tottenham Hotspur and West Ham United are among the clubs to have watched over Valencia midfielder Javi Guerra in recent weeks, sources have confirmed to 90min.
The 20-year-old is enjoying a fine breakthrough season with his hometown club so far, scoring three goals and adding one assist in nine La Liga matches.
He was a bit-part player for Valencia last season but featured in their final ten games of the campaign and helped them stave off relegation to the Segunda Division.
Guerra's superb performances this term have not gone unnoticed and he has been heavily linked with a move away from the Mestalla already.
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Notably, all four clubs were in attendance for Spain Under-21s' 1-0 win against Scotland in Jaen in September, with Guerra playing 45 minutes in the victory.
They are not alone in their admiration of Guerra. Manchester United have made visits to watch Guerra this year though were not at said Spain U21 match, while Barcelona have also looked at the midfielder in the past.
In an interview with the Daily Mail earlier this month, Valencia sporting director Miguel Angel Corona was adamant that Guerra would not be sold.
"We are fully aware that we have a player with enormous potential for the future and the ability to perform at a good level now," he said.
"That is why the club have decisively moved him up to the first team in recent months. It is not in our plans to sell him to any club."
Guerra's contract at Valencia expires in 2027 and contains a release clause which stands at £86m (€100m).