Having laid the groundwork last week, Formula 1 teams are back in Barcelona for the final four days of testing before the season opener in Australia.
For some, it will be a matter of building up from where they left off, for others, finding solutions to the issues which arose in the first week will be critical ahead of Melbourne.
What are the important stories, you should look to follow? Here’s our guide:
Can Williams get back on track?
Certainly, the team will the most to do is Williams having missed the first two-and-a-half days of running last week and only completed 88 laps in total.
Both Robert Kubica and George Russell admitted their focus was on simply putting the team in a position to hit the ground running this week and if Williams can complete a solid four days in line with the rest then some worries will ease.
The question remains, however, just how competitive their car will be and, with spare parts likely to be limited, an answer to that is unlikely until Albert Park.
Ferrari & Red Bull set to go soft
It’s arguable that after week one, Ferrari and Red Bull appear to be F1’s top two in the pecking order having set strong lap times while only using the C3 tyre compound.
This week, however, should see both teams up the pace as they start work on the C4 and C5 rubber, particularly over shorter qualifying-style runs.
That may be hampered by Red Bull running more conservatively than those around them, as is their traditional strategy.
But it will also be vital to see if they do start pushing the Honda engine a little harder after a solid first week which saw it complete over 900 laps and feature well in the speed traps.
Meanwhile, at Ferrari, who were theoretically fastest by 0.4s last week when tyre corrected, they may well continue to push a little harder than their rivals and if they do, don’t be surprised if they top the timesheet comfortably on Friday evening.
Is Mercedes in peril?
One story that has come out since last week is Valtteri Bottas admitting Mercedes do have some fundamental handling issues with the W10 which may require more than simple set-up changes.
Certainly, last week it was noticeable that the world champions didn’t appear at the same pace as their rivals even if they do traditionally run more conservatively in pre-season.
Slow lap times on the softer tyre compounds backed that up, but with new parts expected for the second week, it will be interesting to see if any issues with the Mercedes are as bad as Bottas suggested.
Early design upgrades
It is very often the case that the car which starts testing is not even the same one which races in Australia, with Racing Point already planning a substantial upgrade for the RP19 in Melbourne.
Therefore, don’t be surprised if teams do start to test new parts which have been developed from the initial running last week or weren’t run because of a lack of spares.
This will also be the final opportunity to do preparation work for the first race, so expect more detailed run plans as teams find the nuances of their new cars.
It will also be noted that most teams will look to complete full race simulations with pit-stops included and they often provide the best barometer of who stands where.
The manic midfield
With differing priorities, assessing the midfield in F1 is always difficult in testing with some teams having to run conservatively due to a lack of spares, while others may conduct ‘glory runs’ which seemingly put them in a strong position.
After last week, it appeared little had changed compared to last year with Renault again had the edge while Alfa Romeo and Toro Rosso provided strong competition.
Over these four days, however, the approaches will converge more closely and we’ll gain a better indication of whether Haas, McLaren and Racing Point will also be pushing for Q3 and points in Australia.
As for the initial impressions, McLaren enjoyed good reliability but didn’t appear too quick, Haas was essentially the opposite, while Racing Point completed limited mileage and focused on harder tyre compounds making any assessment tricky!
We’ll be covering all the major stories here at InsideRacing over the second week in Spain and then the countdown will be on until lights out in Australia.