Alvaro Bautista picked up where he left off as he headed both free practice sessions at the Chang International Circuit in Thailand on Friday.
The Spanish rider leads the World Superbike Championship following a stunning debut in the series on the Aruba.it Ducati at Phillip Island in February, where he won all three races on the new V4 R machine.
Bautista holds an advantage of 13 points over reigning champion Jonathan Rea (Kawasaki Racing Team) and the former MotoGP rider put down an early marker ahead of round two in Buriram, topping the time sheets in FP1 and FP2 from the Northern Ireland rider.
He set his fastest lap overall in FP2 in 1m 32.971s, with Rea clocking a time of 1m 33.269s. World Supersport champion and Superbike rookie Sandro Cortese impressed as he put the GRT Yamaha into third (1m 33.465s).
Rea said: "We were building into it this morning and we got off to a good start.
“Step-by-step we improved the bike and were getting into a rhythm in that second free practice session, where we started to make some steps with set-up.
“I wanted to do a consistent long run but we had to confirm which tyre we will use for tomorrow, at the front and the rear. In some areas of this track I also want to improve my braking.
“We found some positives in all that so - putting it together - I felt pretty good out there. We can look at the finer details tonight but already we are on the way.”
Pata Yamaha pairing Alex Lowes and Michael van der Mark were fourth and fifth quickest respectively, while Marco Melandri completed the top six on the second of the GRT Yamaha machines.
Leon Haslam (Kawasaki Racing Team) slotted into seventh ahead of Eugene Laverty, who made a strong start to the weekend on the Team Go Eleven Ducati.
Bautista’s Aruba.it Ducati team-mate, Chaz Davies, was 11th behind Leon Camier (Moriwaki Althea Honda) and Tom Sykes on the factory BMW, with the Welsh rider over a second off the top time.
In FP1, Bautista also had the edge with a lap of 1m 33.089s from Rea, who lapped in 1m 33.288s.
Race one takes place on Saturday at 09:00 GMT at the Chang circuit, where Rea has won six of the last eight races.