The Argentine says the 22-year-old provides hope to the club's budding stars and was delighted with their resolve demonstrated in their latest Primera Division success
Goal understands Manchester United are admirers of the midfielder and had sent officials to Spain in the hopes of brokering a deal to sign the player, before moving for Juan Mata.
And Simeone is hoping that the 22-year-old becomes an icon for Rojiblancos youth team players for years to come.
"He is a guy with a huge future," Simeone is quoted as saying by AS. "He gives us many solutions in games and is an example to the guys pushing from below [the first team]."
Reflecting on the match, Simeone was happy with his side's performance against a plucky Vallecano outfit.
"It was a difficult game at a difficult stadium because Rayo are a brave team who are not afraid to play," he continued.
"We did ery well for th first half hour, but then they balanced the game out and scored their goal. Being 3-1 up at half-time was not bad.
"This is a very positive result. This team solved a problem that didn't seem easy."
David Villa and Saul scored either side of Arda Turan's double for the Copa del Rey holders at Vallecas, with Jonathan Viera and Joaquin Larrivey netting for the hosts.