Reigning MotoGP world champion Casey Stoner missed out on a front row start at Sepang by just two tenths of a second, but the Repsol Honda star is far from happy.
Stoner, who made his comeback from injury at Motegi last weekend, said his potential is 'much higher' than his fourth position on the grid reflects.
The Australian rider is frustrated by a lack of progress with his RC213V during practice and qualifying and is now braced to enter the Malaysian Grand Prix 'without any real direction'.
“It's been a really disappointing weekend, but especially today,” he said.
“We've had pace all weekend and the first session looked promising but we've had problems with the brakes and some other small issues.
“Every step we take to try and improve the bike, we make it worse and it's becoming very frustrating.
“Our potential is much higher than where we are currently at and now we go into the race without any real direction,” added Stoner, who will quit motorcycle racing following the final race of the season at Valencia next month.
“Physically I'm not sure how I am going to be as we haven't been able to complete many laps this weekend - our pace is there and I just hope that we can make some small improvements in tomorrow's warm-up.”
Stoner's best lap in 2m 00.811s was 0.477s behind Jorge Lorenzo's record pole time.
On his comeback from injury at Motegi last weekend, Stoner finished fifth, 20 seconds behind team-mate Dani Pedrosa.
He remains in third place in the championship after missing three races with ankle fractures and ligament damage after a heavy fall at Indianapolis, but is now just five points ahead of satellite Yamaha rider Andrea Dovizioso in the standings.