The attacking midfielder played up front in the final fixture as Getafe secured the point they needed for survival.
Ciprian Marica scored twice for Getafe with Roberto Trashorras responding for Rayo Vallecano, who finished 13th of 20 teams in Spain's top flight.
Yago, on a season-long loan, made 31 appearances for Rayo including 28 in La Liga, where he scored three times.
Elsewhere, Jake Livermore played the full 120 minutes as Hull City stormed into a 2-0 lead in the FA Cup Final only for Arsenal to haul them back to 2-2 before grabbing the winner in extra time.
Grant Ward has joined up with Chicago Fire in the MLS after injury delayed his loan. He wasn't involved this weekend as the Fire - who we take on as part of our summer tour of the US and Canada - toppled reigning MLS Cup champions Sporting Kansas City on Sunday.
Finally, Tom Carroll is preparing with the QPR squad for Saturday's huge Championship play-off final against Derby County at Wembley.