A jet-lagged Carlos Checa admits he was surprised to come away from the opening day of World Superbike testing at Phillip Island clutching the fastest time, the Spaniard once again edging his factory-backed Ducati counterparts.

The former Ten Kate Honda rider was fastest during testing at Valencia earlier in the month, Checa carrying that form to Australia to end the first of two days almost four tenths faster than Michel Fabrizio on the manufacturer prepared Ducati 1198.

Further indication that the Althea Racing team will be a force to be reckoned with in its first season with the Ducati, particularly as Shane Byrne shadowed his team-mate in fourth, Checa was thrilled to see himself on top again.

"It's really surprising for me to score the best lap time here in Phillip Island in my first day of testing with my new bike and my new team," he said. "I also reached first position in Valencia, but doing it here is more significant to me because I'm a bit tired due to jet lag.

"In Portimao I wasn't able to take advantage of the soft tyre, but today I understood how to use my Ducati with a softer rear tyre. I want to thank all of my technical staff because they helped me immensely with their elevated experience and know-how with Ducati bikes. On day two I'll be testing some new components and I'll definitely try to improve my race pace."