Bebe has not closed the door on a possible return to Manchester United or another big club in Europe.
Prior to that, Bebe was purchased by United as a virtual no-name from Vitoria de Guimaraes in 2010 and despite falling well short of the standard during his spell at Old Trafford, suggests he can still make the step up to a massive club.
"I've never thought about that [returning to Man United], but nothing is impossible," he told Portuguese newspaper Publico.
"If I score 10 goals in La Liga then for sure, I'll be able to sign for a big club.
"If I score 10 goals here at Rayo Vallecano I'm going to have many big teams chasing me again next year."
So far this season, Bebe has made six league appearances for Vallecano, scoring once in a 3-2 loss to Sevilla.