McLeish said: "I need to speak to Mauro about that (the dive). It's in the culture of the South Americans, the Latins especially. I need to tell him it's well scrutinised over in this country.
"But I was pleased with his performance. He was exciting at times. It was difficult for him to come in under the circumstances with James McFadden having missed out the preparation due to his wife having a baby.
"With Portsmouth having such class players at the back, it wasn't going to be easy. But I thought Mauro acquitted himself well and he's only 20.
"Ideally he needs time to settle in. We probably expect miracles of him but he will cause teams problems between now and the end of the season."