Hopkins heads home for treatment.

The Anglo-American now faces a race against time to be fully fit for the final pre-season test, at Qatar from February 28-29, or at least by the season opener on March 9.

"Riding in the rain yesterday took its toll on my injury and today I have definitely felt the effects," said John. "With our focus firmly on the first race, we decided it wasn't necessary to go out on circuit this afternoon. I am flying home [on Tuesday] to immediately have as much therapy and ultra-sound treatment as possible to maximise my recovery."

Team-mate Anthony West was thus left to shoulder much of the final day ZX-RR test schedule - and set the 12th fastest lap time with a qualifying tyre.

"We've mainly worked on the handling and the steering of the bike today," explained the Australian. "We've made a big step forward in the front-end set-up and I feel a lot more confident, although there is still room for further improvement. We have also tested some qualifying tyres from Bridgestone that I have never used before and the results were promising, I am sure that given more time using them we could have gone even faster.

"We finished off the test with a 10-lap run to see what the tyre performance is like towards the middle of race distance and we found more consistency than with the previous tyres we have used. We now have a plan to fine-tune the set-up with what we have learned here in Jerez and I will return home to continue with my training programme before heading to the last pre-season test in Qatar," concluded Ant, who is seeking to improve his fitness in time for the first race.