Verdiblancos moved up to sixth in La Liga with the one-sided victory against Mel's former team, whom he wished luck in their fight against relegation.
"We did not expect to win by this result," Mel told reporters. "At Granada I wish them luck, you know that I have affection for this club.
"We will now look to European places. Today we have taken another small step."
Valencia could retake sixth position with victory over Valladolid on Sunday.