Checking through your predictions this morning and it is clear to see 99% of you are anticipating another year of Mercedes dominance. 

So what can stop them this season?

I'll kick things off with: 

#ifanythingcanstopmercedes, external it is Chuck Norris...

Image source, Getty Images

And he'd beat them in one these too...  

Image source, Getty Images

Sebastian Vettel improves at the top of the timesheet. He's got unmarked mediums on his Ferrari and posts a 1:24.628, increasing the gap between himself and Valtteri Bottas in second to 0.7s.

Think we will leave that topic in yesterday's coverage but given the brilliant randomness of this suggestion, I'll allow it today.

Image source, PA

Alright for some isn't it? 

Plenty of the white stuff about in areas of the UK this morning. I guess that why's they go testing in Barcelona...

F1 journalist Dan Knutson in Barcelona: "Daniel Ricciardo is back in the pits. He has completed 20 laps but not set a time because of all the pit stop practice. The crew certainly got a good workout."

The Sauber does indeed head out, so everyone has had some time on the track this morning.

Meanwhile, Valtteri Bottas moves up to second after posting 1:25.328 with medium tyres on his Williams. 

Once again it is the Mercedes that has been putting in the most mileage this morning because Lewis Hamilton is onto 28 laps. 

One driver has yet to make an appearance on the track, but he's about to rectify that now.

Bold from Steven here.

F1 journalist Dan Knutson in Barcelona: "Red Bull is doing a series of tyre change pit stop practice. Here Daniel Ricciardo smokes the tyres as he leaves the pit stall. 

"Christian Horner is timing it all from the pit wall – using a Tag Heuer stopwatch no doubt..."

Staring contest, eh?

Anyone remember '90s comedy Big Train? Any mention of a staring contest and I can't help but remember the brilliant randomness of Barry Davies commentating of two cartoon sketches staring each other out.

What a show that was.

Anyway, I digress. Lewis Hamilton has just jumped up to fourth following a 1:27.235, putting him just behind Jenson Button, who posted 1:26.833 a little earlier.

Sergio Perez's first timed lap is a 1:26.491, putting him into P2 behind Sebastian Vettel while Pascal Wehrlein is up and running in the Manor with 1:29.621, the seventh fastest time.

Still waiting on three drivers to put down their first timed effort of the day - Daniel Ricciardo, Esteban Gutierrez and Marcus Ericsson.

Plenty of you are optimistic that McLaren will make a big step forward this season. Rich, below, is particularly optimistic!

Image source, Getty Images

Lewis Hamilton has been running with aero rakes fixed onto his Mercedes.

I suppose that is one way of slowing them down...

After a brief spell in the garage, Hamilton has just been back out for a couple of laps while Jenson Button, who has moved up to fifth with a 1:28.331, stops at the end of the pitlane to do a practice start.