The Baggies are just three points above the bottom three in the table with eight games left to play.
They will take on Cardiff City, who are also fighting against the drop, at The Hawthorns on Saturday.
"[Relegation] is not a situation that comes into my head," Mel told reporters. "I am far more optimistic. For us there is only one game. Cardiff is the final. The only thing that will do for us is a victory."
West Brom have secured just one win since Mel's appointment on January 9.