Ruiz's stock has risen significantly during his breakout season at Betis, who currently lie 11th in the La Liga table. The technically gifted 21-year-old's performances have helped Quique Setien's side to banish any lingering thought of a relegation battle this season and have certainly not gone unnoticed by clubs around Europe, with David Moyes' side pondering a move before the end of the January transfer window, according to the Telegraph.
Moyes is still hoping to strengthen his central midfield options before the end of the month and a deal for Ruiz would be well within their means due to the €15m (£13m, $18.6m) release clause included in his current Betis contract, which expires in 2020.
West Ham are certainly not the only Premier League club interested in the young Spaniard, though; El Confidencial claim that scouts from Everton, Arsenal, Chelsea and Newcastle United have watched Ruiz with increasing regularity, and they may be encouraged by his agent's reluctance to bow to Betis' demands and increase the midfielder's release clause.
Betis are determined to hold onto Ruiz, who is also said to have caught the eye of Real Madrid and Barcelona, and are preparing to offer their coveted starlet a much-improved contract which would see his release clause rise substantially.
Everton have numerous central midfield options to choose from at present, but with doubts over the form of Morgan Schneiderlin, James McCarthy set for an extended period on the sidelines and Muhamed Besic expected to leave, Sam Allardyce's side may see fit to replenish their engine room in the coming months.
West Ham boss Moyes has exhausted many options during his quest to find a new midfielder this month, though a deal for Inter Milan's Joao Mario finally looks as if it will go ahead. Setien, whose brand of football has reinvigorated Betis since he took over in the summer after leaving Las Palmas, does not want to see Ruiz leave for the Irons or indeed any other interested party, insisting that the best place for his development is the Villamarín.
"It is not the moment for Fabian to leave Betis," Setien said. "It's time for him to grow up here, now that he plays in a stable club and a team with a phenomenal way of playing that has grown in four months more than it has grown in twenty years."