The Spaniard takes charge of his first match with the Baggies on Monday against Everton at The Hawthorns, and his compatriot feels that he will do a fine job at the midlands outfit.
"I think he will surprise a lot of people. He has been very successful in his time in Spain," said Martinez in his press conference. "The first time I was aware of his work was at Rayo Vallecano when he got them promoted to the top league against the odds with a very small budget and since then he has done a remarkable job wherever he has been.
"It is probably the wrong time to face Pepe Mel, but we wish him the best of luck after Monday. I can see this West Brom side being a different one to what has been so far this season.
"We know their players really well, but they will do things differently. But we will concentrate on ourselves and try to be as good as we can in the things we do."
The match gets underway at 8pm.