The Spaniard tipped his countryman Michu, arguably the signing of the summer, to break into the formidable Spain national side.
Martinez said: "They (Swansea) deserve a lot of credit. Now they can go into the second leg with a real optimism and desire to get closer to that opportunity to be at Wembley.
"I think Michu will very soon go to the national team. To get that achievement it shows you what a season he's having because you're looking at trying to get into the best team in history.
"I think he's done really, really well, I think it was the perfect moment in his career to come to the British game. He can go a long way."