Ferrari has another troubled F1 test as McLaren goes quickest again on day six

MONTMELO, Spain -- McLaren finished fastest for the second day in a row in the final week of preseason testing at the Circuit de Catalunya as Ferrari faced its second setback in as many days.

Carlos Sainz improved by over half a second on Lando Norris' best time from Tuesday to set a new preseason lap record for the Circuit de Catalunya. The time -- 1:17.144 -- was still a second off the ultimate lap record set during qualifying for last year's Spanish Grand Prix, but acted as further proof of a resurgent McLaren after a solid preseason so far.

Sainz was using Pirelli's second-softest tyre compound -- known as the C4 -- which suggests there is still more to come from the McLaren on the very softest rubber. It left Sainz comfortably fastest by 0.698s from Racing Point's Sergio Perez, while the top teams continued to mask their true pace on the softer tyres.

Ferrari's track time was severely limited by a high-speed accident in the morning involving Sebastian Vettel. The four-time world champion walked away from the crash uninjured, but the car was left wrecked and only completed a single lap in the afternoon. The team later confirmed the crash was caused by a wheel rim damaged by a foreign object on the approach to the high-speed Turn 3.

The issue was Ferrari's second problem in as many days after checks to the cooling system cost Vettel's teammate Charles Leclerc track time on Tuesday. Despite completing over nine race distances in the first week of testing, Vettel said the lost laps were still a concern.

"Well we covered a lot of mileage last week but surely the plan is always to fulfil your programme," he said. "We had more laps on the board than 40 this morning so for sure it is not ideal in that we are losing time.

"But right now it is important to understand what happened. I hit the wall quite strongly and I think the Tecpro and the wall did their job and the car did its job but of course after the impact the car was very damaged. That's what also makes it quite difficult to reconstruct what was going on just before the impact."

The car was rebuilt in time for Leclerc to complete just a single installation lap before the chequered flag.

A further three red flags stopped running during the day, with a loss of water pressure causing Sainz's car to stop on track in the morning, Max Verstappen coming to a halt at the pit lane exit and Kimi Raikkonen's Alfa Romeo stopping on track in the final minute of the session.

After a power-unit problem kept Mercedes in the garage for the majority of Tuesday afternoon, the world champions made up for lost time on Wednesday with a total of 176 laps between the two drivers. Lewis Hamilton completed the lion's share with 104 laps in the afternoon to add to Valtteri Bottas' 72 in the morning.

Once again, Mercedes' lap times were not hugely impressive after both drivers set their best time on C3 compound to finish eighth and ninth. Only Renault -- splitting track time between Daniel Ricciardo and Nico Hulkenberg -- and Williams were slower, although all three teams completed good mileage.

Times at close:

1. Sainz, McLaren, 1:17.144, 130 laps

2. Perez, Racing Point, 1:17.842, 88 laps

3. Vettel, Ferrari, 1:18.195, 40 laps

4. Raikkonen, Alfa Romeo, 1:18.209, 113 laps

5. Grosjean, Haas, 1:18.330, 120 laps

6. Verstappen, Red Bull, 1:18.395, 128 laps

7. Kvyat, Toro Rosso, 1:18.682, 101 laps

8. Bottas, Mercedes, 1:18.941, 74 laps

9. Hamilton, Mercedes, 1:18.943, 102 laps

10. Hulkenberg, Renault, 1:19.056, 58 laps

11. Kubica, Williams, 1:19.367, 130 laps

12. Ricciardo, Renault, 1:19.367, 72 laps

13. Leclerc, Ferrari, No time, 1 lap