PAISLEY, SCOTLAND - JULY 01: Tomas Rogic of Celtic in action against Den Bosch during the Pre Season Friendly between Celtic and De Bosch at St Mirren Park on July 01, 2015 in Paisley, Scotland. (Photo by Jeff Holmes/Getty Images)

RenaultF1 concluded their penultimate day of pre-season testing with Jolyon Palmer at the wheel of the R.S.17 at the Circuit de Barcelona-Catalunya.

The British driver completed a total of just 31 laps in the morning with his best lap time of 1:22.418 the then eighth fastest time.

He returned to the car in the afternoon and completed a further 22 laps.

During the course of the session, his car underwent an engine change, limited Jolyon's mileage to just 53 laps.

“We have a completely new power unit for 2017 and we have been mileage-limited with an element on the ERS side this week,” explained Remi Taffin, engine technical director at Renault. “We saw some similar issues in development on the dyno, however testing on track has magnified this."

"Fixes are already underway and we expect to have them in place for Melbourne so we achieve the appropriate level of reliability for the start of the season, however this has impacted on our running here in Barcelona. In terms of performance we are satisfied we have taken a positive step forward and there is more to come over the season ahead. We are learning with every day with the car, so it is a case of continual progress.”

Fast Facts:
Track: Circuit de Barcelona-Catalunya, Spain, 4.7km
Chassis: R.S.17 - 01
Weather: Mild to warm and sunny. Ambient 9°C - 20°C Track 17°C - 33°C
Programme: Assessments and evaluations.
Laps Completed: 53
Classification: P10, 1:22.418
Interruptions: Power unit change.

“It was rather frustrating today with interruptions from our side and also with other disruptions on track too,” Jolyon said. “We never seemed to be able to get into a rhythm and I didn't get the same feel with the car that we had previously. We're having a good look at the data to understand where we need to improve as we know the scope and potential is there. I'm hoping for a better day to end the test tomorrow.”

Both drivers are scheduled to be back in action later today for the final day of pre-season testing, with Nico taking to the wheel first.