Rossi critical of April Motegi date

The event moved to April this season for the first time since its debut in the championship in 1999, having been held in September or October from 2000 to 2008.

The reigning world champion will start Sunday's race from pole position, thanks to setting the quickest time in Friday's dry practice session, but was frustrated by the conditions just two weeks after the opening race of the season in Qatar had to be delayed until the Monday due to heavy rain.

"It's a disaster," said Rossi. "The last years we have been very unlucky with the weather in Japan, but an April grand prix at Motegi is not a good idea because the weather is always quite bad.

"It's an unbelievable situation, at more or less every GP now there is rain. Qatar was bad and this is a disaster. I am ready, but it would be difficult to go like this because there is so much water. It was difficult already by the end of practice this morning and now it is just impossible, there's too much water.

"There was just one practice each day and I am lucky that I did the best time because to start from pole is really important for the race tomorrow. We have to wait to see the condition of track, if it's wet or dry. I am happy because I am fast in both conditions, but we hope for good weather."