The Hawthorns outfit find themselves perilously placed just three points above the relegation zone after a wretched run of form that has seen them win only one of their 10 matches under Mel.
That victory, a 2-1 success at Swansea City earlier this month, has kept them out of the bottom three for now, but improvement is needed if West Brom are to retain their top-flight status.
A crucial home fixture against fellow strugglers Cardiff City awaits Mel's charges on Saturday and the Spaniard knows that it represents a crucial game.
"This (relegation) is not a situation that comes into my head. I am far more optimistic," Mel said.
"We need the spirit we had against Swansea. We've been conceding too many early goals.
"We need that extra effort against Cardiff.
"For us there is only one game. Cardiff is the 'final'. The only thing that will do for us is a victory."
Mel has a series of injury problems to contend with, and striker Victor Anichebe is his major concern.
The powerful forward suffered a hamstring injury in West Brom's 2-0 loss at Hull City on Saturday.
"There is a question mark over Anichebe," Mel added.
"We will see how he is tomorrow (Friday). We are waiting to find out on Anichebe, but we need to make sure we are strong defensively. We've conceded too many goals."
Morgan Amalfitano is available again following a knock, but Billy Jones and Claudio Yacob will both miss out after suffering hamstring injuries.
