For Nagashima, riding in place of the injured Iker Lecuona, it was also his first ever WorldSBK race.

The HRC test rider was an impressive sixth in Friday practice, at a track where he subbed for countryman Takaaki Nakagami on an RC213V MotoGP machine last month, before his progress was stunted by a Turn 1 fall in the wet on Saturday morning.

Nagashima return to qualify just behind Vierge for tenth despite another accident in the dry Superpole, before more showers soaked the track for the start of race one.

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Nagashima return to qualify just behind Vierge for tenth despite another accident in the dry Superpole, before more showers soaked the track for the start of race one.

The pair held seventh and twelfth in the wet opening stages, before improving conditions prompted mid-race pit stops. Vierge was momentarily promoted to fourth and Nagashima seventh, before HRC own stops dropped the pair to tenth and 15th.

The dry final closing stages saw Vierge gain two places and Nagashima advance five positions for eighth and tenth at the chequered flag.

“The race was a crazy one, my first ever flag-to-flag race,” said former Moto2 rider Vierge. “During the first part, we were too slow in the wet, making too many little mistakes; it was very challenging.

“When I entered the pits, the team was ready and they worked fast, allowing me to re-join the race in a good position and achieve a fairly good result.

“We learned a lot today too, both for the future but also for tomorrow as the forecast is again looking uncertain and conditions can change by the minute.”

Nagashima, at a loss to explain his FP3 fall, built confidence as the race progressed.

“Today was very tough with the two crashes this morning,” he said. “Conditions were particularly critical in FP3 but I still don’t know how I crashed.

“As for the race, I didn’t push too much straight away in the wet, and I lost a lot of time and positions as a result. Lap by lap my rhythm improved, and, after the tyre change, I felt even better and my lap times weren’t so bad.

“I was able to make a few passes and reach tenth place.

“Experiencing a flag-to-flag race and such tricky conditions in my first Superbike race wasn’t ideal of course, but it is what it is, and I think it’s all good experience anyway.

“I want to say a big thank you to the team because they did an amazing job of repairing the bike before the race and it worked perfectly. Now we will check all the data and prepare for tomorrow.”

Sunday’s schedule will see the short Superpole race followed by a full-length race 2 season finale.