Sebastian Vettel claimed the top spot on the timing sheets on the penultimate day of Formula 1 pre-season testing for Ferrari as he lapped the Circuit de Barcelona-Catalunya in 1:19.024 – the fastest of testing so far.
Vettel completed his best lap on the ultrasoft compound, but could potentially have gone quicker as he backed off on the exited the final corner, slowing as he approached the finish line on several of his fast laps.
Had he pushed, Vettel would have dipped into the 1:18s, but his time was nonetheless sufficient for him to finish on top, completing 156 laps in the process, via a race simulation in the afternoon.
Lewis Hamilton was second quickest for Mercedes, just over three-tenths adrift of Vettel's best time on the same tyre – with both drivers setting their times during the morning running.
Hamilton's lap was just a few thousandths shy of his team-mate's best lap from Wednesday, which came on a supersoft run.
Despite Vettel's superior pace, he has played down claims Ferrari are favourites heading into the opening race, instead claiming Mercedes remain the team to beat, particularly on the longer runs.
Completing the fastest three times was Force India's Esteban Ocon, who posted a 1:20.161 to finish a second slower than Vettel.
The day featured four red flags with McLaren suffering yet another troubled day as Stoffel Vandoorne stopped twice during the morning due to an electrical issue
The Belgian managed to run during the afternoon, joining midway through the session, but only completed a total of 48 laps, leaving McLaren at the foot of the mileage charts.
Vandoorne was seventh quickest, behind Daniil Kvyat, Kevin Magnussen and Daniel Ricciardo, with Valtteri Bottas eighth for Mercedes, having taken over from Hamilton for the afternoon session.
Renault-powered Kvyat and Jolyon Palmer were the cause of the other two red flags.
Williams focused on long runs with Felipe Massa and Lance Stroll, finishing at the bottom of the times, but at the top of the combined mileage charts with 165 laps.
| Pos | Driver | Team | Time | Gap | Tyre | Laps |
| 1 |  Sebastian Vettel |
Ferrari | 1:19.024 |  |
156 | |
| 2 |  Lewis Hamilton |
Mercedes | 1:19.352 | 0.328 | |
52 |
| 3 |  Esteban Ocon |
Force India | 1:20.161 | 1.137 | |
137 |
| 4 |  Daniil Kvyat |
Toro Rosso | 1:20.416 | 1.392 |  |
94 |
| 5 |  Kevin Magnussen |
Haas | 1:20.504 | 1.480 | |
119 |
| 6 |  Daniel Ricciardo |
Red Bull | 1:20.824 | 1.800 | |
128 |
| 7 |  Stoffel Vandoorne |
McLaren | 1:21.348 | 2.324 | |
48 |
| 8 |  Valtteri Bottas |
Mercedes | 1:21.819 | 2.795 |  |
95 |
| 9 | Pascal Wehrlein |
Sauber | 1:22.347 | 3.323 | |
44 |
| 10 | Jolyon Palmer |
Renault | 1:22.418 | 3.394 | |
53 |
| 11 |  Marcus Ericsson |
Sauber | 1:23.330 | 4.306 | |
88 |
| 12 |  Felipe Massa |
Williams | 1:24.443 | 5.419 | |
80 |
| 13 |  Lance Stroll |
Williams | 1:24.863 | 5.839 | |
85 |
