Foggy Petronas Racing riders Craig Jones and Steve Martin face an uphill battle to qualify for Superpole after a challenging opening day to the ninth round of the Superbike World Championship at Assen, Holland.

Jones made huge strides forward during the afternoon qualifying session, bettering his free practice time by more than three seconds on his first meaningful visit to the circuit.

Martin was hampered in learning the new shorter circuit lay-out when a series of mechanical problems denied him essential track time.

He finished 22nd in the standings with a time of 1:42.443, with Craig just half a second behind with a time of 1:43.052. Troy Bayliss set a blistering pace with a lap of 1:39.336 in cool, overcast conditions.

Jones said: "It's hard to come to a new circuit and set a bike up from scratch, and the fact that there is a new lay-out meant we didn't even have any data from last year.

"So I didn't really know what I wanted the bike to do early on. But I took more than three seconds off my time in the afternoon and we have a direction to follow.

"I want to continue learning because the further up the grid I can get the better the chance I will have in the race, and this looks like a circuit with a lot of passing opportunities."

Martin said: "We have had a lot of problems throughout the day and I have had to walk back to the garage on two occasions."