Robles, who joined the Latics on loan until the end of the season from Atletico Madrid last week, kept a clean sheet despite almost constant bombardment from Macclesfield in the second half as Wigan triumphed 1-0.
The 6ft 5in keeper will now compete with Ali Al Habsi and Mike Pollitt for a regular starting berth in the Barclays Premier League, with Saturday's performance only helping to stake his claim.
Martinez said: "I thought he did really well. It doesn't get more challenging maybe than making your debut in the FA Cup fourth round away from home.
"I thought he was superb. He didn't get caught by the event. He communicated well and his decision-making and distribution was outstanding.
"I think we saw a couple of flashes of the phenomenal goalkeeper that he is and we are delighted to give him this sort of welcome to the English game."
Robles, 22, made 13 appearances last season on a loan spell at Rayo Vallecano as well as featuring twice for Atletico.
- Sports & Recreation
- Barclays Premier League
- Mike Pollitt
- Atletico Madrid
- Ali Al Habsi