MotoGP title runner-up Andrea Dovizioso completed his final day of 2017 track action on top of the timesheets at the private Jerez test.

Third quickest on day one, the Ducati rider lowered his lap time by 0.735s courtesy of a 1m 37.663s, set during a short run of two flying laps.

That time is also comfortably below the official Jerez lap record, thanks in part to the new asphalt. LCR Honda's Cal Crutchlow was 0.155s slower than Dovizioso, whose team-mate Jorge Lorenzo was +0.258s in third.

As at the Valencia test, the Ducati riders were trying some new parts on their GP17, as the factory seeks to finalise the design of their GP18, which is expected to debut at Sepang in January.

"We have a few things to try just to fix the 2018 bike," Dovizioso told the official MotoGP website. "But we didn’t have a lot of stuff. It was good to test in Jerez because there is a new asphalt and the track changed a lot. It is much faster.

"We did a really good lap time. It was nice to ride in this condition. But apart from that we just compared a few things. We tried everything we wanted to. Now we will start the winter break."

Dovizioso, winner of six races this season, gave little away regarding the GP18 but did reveal that the parts so far tested did not have a noticeable impact on Ducati's last remaining weakness; turning.

"We improved a little bit, but not our limit and our limit started from a long time, we never really fixed it, is the turning," he said. "So what happened at Phillip Island, a track where you don’t have to use a lot of brake, the bike doesn’t turn as good as the competitor and we have to be focussed on that.

"Still the turning is our negative point and where we have to improve more. Apart from that our base is quite good, depends on which track, but our bike is quite good with the tyres and the electronics are quite good. So mainly I believe it's the turning."

While Dovizioso and Lorenzo have concluded testing, Pramac's Danilo Petrucci is expected to put laps on the hybrid GP17-18 bike during Friday's final day at Jerez.