Fernando Alonso believes that Ferrari have made good progress following a promising display in practice for the United States Grand Prix.

After finishing sixth in first practice on Friday morning, the Spaniard registered the third-fastest time in FP2 and Alonso is adamant that improved levels of grip helped the Italian constructor.

He told reporters: "Today we did some good testing, helped by the track conditions, which were definitely different to previous years. It's possible the races they had here a few weeks ago helped to clean the track and as far as grip levels were concerned, we didn't have too many problems.

"In the second session, the situation was slightly worse because of the strong wind, but that was expected over the weekend and did not affect our work too much.

"Certainly the race looks like it will be different to past editions, because the likelihood of two stops opens up different strategic possibilities."

Alonso's future remains uncertain after being heavily linked with a move to McLaren, who will be powered by Honda engines from 2015.