Honda 'paying attention to' Andretti

"It was a last-minute decision to come here," de Ferran told the official IndyCar Series website.

"I was at the office in England on Friday and we flew over here with my family for a little vacation and we decided to come over to the race and see these guys.

"I think Marco is one of the bright young stars. He has shown tremendous potential at an early age. The people he's racing against are very good. We would be remiss if we weren't looking at promising talent from around the world.

"Marco is very mature and a very intelligent guy. He's very much in control of his world and his situation and that impressed me a lot. He's a tremendous talent in the car but his attitude and his head impressed me the most."

The 20-year-old American has been widely-tipped as a future Honda F1 driver after testing for the team twice during the winter, although Andretti maintains that he will see out the final two years of his Andretti-Green Racing IRL contract.

De Ferran confirmed that Andretti would remain in the USA for now, but also that Honda would continue to follow him closely.

"Marco is with a great team here in IndyCar and is focused on winning over here, that's the target right now," de Ferran said. "He's one of the bright young talents and we would not be doing our job if we weren't paying attention to who is coming up."

Andretti qualified fourth at Homestead but retired early with severe handling problems.