Mercedes driver Nico Rosberg has claimed that he is worried about Ferrari's pace ahead of this weekend's Bahrain Grand Prix.

Rosberg set the pace in practice yesterday, and will look to beat teammate Lewis Hamilton to pole position later today during qualifying.

Ferrari showed good pace during yesterday's sessions, and Rosberg told Sky Sports F1 that their opposition's race pace is something of a concern.

"Confidence is good, it was a good day today. Of course lunchtime was a bit useless because it is so hot and the race is in the evening so we don't learn much," he said.

"So it has been good, but the pace of the Ferraris is very worrying. In qualifying we are again much quicker, but in the race they are quick."

Rosberg is currently third in the standings, 17 points behind first-placed Hamilton.