Prema mystified by Hungaroring European F3 tyre dramas

Nick Cassidy, the championship leader heading into Hungary, suffered huge blistering to his Hankook rubber in second qualifying and the first two races.

The same problem also struck Lance Stroll during the second qualifying session, but team-mates Maximilian Gunther and Ralf Aron were unaffected throughout the weekend.

Cassidy's laptimes went out from 1m36s to 1m40s within the space of four laps as he tried to defend seventh place in race one, and he gave up with six laps remaining as he felt it was too dangerous to continue.

His tyres for race two, including two-brand new Hankooks, were already blistering on the reconnaissance laps to the grid.

The Hungaroring's brand-new track surface came under suspicion for the problem - Esteban Ocon's pole position record was broken by two seconds - but it was the inconsistency across its cars that puzzled Prema.

"It's difficult for me to understand," said Rosin.

"All four cars are exactly the same in set-up, and we have two cars that are fast and two cars that are embarrassing.

"Lance was outstanding in testing and free practice, and it's difficult for me to get an explanation - we are still analysing everything."

"We think it's mainly due to the asphalt - compared to 2014 [F3's last visit to the Hungaroring] we are much faster than the old car.

"Track temperatures are hot, but nothing that we never reached before."

Cassidy's pace was so slow as second qualifying wore on that rival George Russell, who was behind him on track, believed that the New Zealander was deliberately baulking him in the wake of the alleged Paul Ricard team-orders controversy.

Russell himself suffered exactly the same problem as Cassidy in race one, his laptimes dropping from 1m36s to 1m41s as he defended the lead, while Hitech GP team-mate Ben Barnicoat was unaffected.

After retiring from race one, Cassidy said: "It's bullshit - we changed completely the car and the warm-up procedure.

"The tyres would have exploded with three more laps.

"I've got no tyres left - if [Sunday] is dry I won't be able to start because the only tyres I have left are throwaway."

Sunday was wet, allowing Stroll to recover from eighth on the grid to third.

"Qualifying was a bit strange - I didn't expect the pace to be like that," said the Canadian.

"We need to figure out what happened, but it's important that we recovered at the end."

CASSIDY TO RACE AT RED BULL RING AFTER ALL

Cassidy will now not miss May's Red Bull Ring European F3 round.

His Super GT commitments to the TOM'S Lexus team take priority and there was a clashing round at Autopolis, but this has been postponed to a yet-to-be-decided date in the wake of the Kumamoto earthquake tragedy.