The scores on the door tell the tale, while Ferrari and Mercedes have completed 86 laps apiece this morning, and Red Bull 85, McLaren has competed just 7, posting a best time 4.377s off the pace.

The first sign that there might be an issue was early on when Stoffel Vandoorne came out for his installation lap and stopped at the end of the pitlane necessitating rescue by his crew.

The Belgian remerged almost an hour later but then stopped on track at the start of the pit straight, bringing out the red flag.

Shortly after McLaren revealed: “We suffered a power shutdown during Stoff’s last run, meaning we lost data. The team are investigating, but we’ll be back out as soon as we can.”

In fact he didn't reappear until the moments before the lunch break, completing a handful more laps without failing to improve his time.

No such problems for the usual suspects however, with Valtteri Bottas, Sebastian Vettel and Max Verstappen - standing in for an unwell Daniel Ricciardo - completing over 80 laps apiece while also leading the way in terms of pace.

Sporting a 'shovel wing' underneath his nose (don’t go there), Bottas was pace-setter for much of the morning, posting his best time on the soft rubber.

Interestingly, Vettel's best time - the morning's benchmark - was set towards the end of a long stint on the medium rubber, while Verstappen's best also came on the white-banded tyre.

McLaren's difficult morning will clearly not have been helped if the Woking outfit were to look further down (or rather up) the pitlane, where Pierre Gasly posted the fourth best time of the morning. His best time, just 0.577 off Vettel's pace, combined with the fact that he has completed 53 laps suggests the Faenza outfit has pace as well as reliability.

While they all appeared to get off to a slow start, by the end of the morning Haas, Renault, Williams and Sauber had settled down, Marcus Ericsson making a late improvement to leapfrog Sergio Perez.

The Mexican was the cause of the morning's second red flag after spinning at T4 and leaving debris on the track. Even so he was able to return to the pits and the session was green-flagged shortly after.

An interesting morning which started with the usual array of garden gates strapped of the cars and then morphing into lashing of flo-vis.

After last week's shenanigans the weather gods were clearly playing ball, with bright sunshine and temperatures hitting 16 degrees.

We've a long week ahead, and while the usual suspects will be buoyed by this morning's running, others, especially McLaren, clearly have much work to do.

Check out our Tuesday gallery from Barcelona, here.