Given Mercedes outstanding reliability which has led to 'unprecedented testing mileage' , the German manufacturer decided to change its testing plans today by allocating to each of its drivers a half-day of running.
Mercedes purpose is to spare both Nico Rosberg and Lewis Hamilton the physical wear and tear of a full day of testing. Hamilton racked in 156 laps on Monday while Rosberg clocked in with 172 laps under his belt yesterday.
Each driver's mileage for the day has therefore been reduced to avoid any physical strain before next week's test and the subsequent first race in Australian.
Rosberg appeared on Facebook last night for an informal Q&A with his fans. Answering a question about why his eyes looked so red, the German explained that the exposure and sheer time spent in the car had taken its toll, although he insisted he felt perfectly fine.
Speaking at an event in Barcelona, Lewis Hamilton acknowledged that his return to the cockpit on Monday and the subsequent workload had been tiresome.
"I feel pretty good today, but I'm sore," said Hamilton.
"When you drive the Formula 1 car for the first time, it doesn't matter how much you train, it's like doing a workout. If you haven't been to the gym for a couple of months, the next day you have that soreness. It's exactly the same.
"The back of my neck, because of the G-forces we are pulling is crazy, so my neck, I'm feeling it, and my lower back. Tomorrow [Wednesday] I guess we're going to be doing even more laps - I think the target is 180.
"What's crazy now is we have a lot less test days. When I first joined F1 at the end of 2006 and beginning of 2007, we had 20 days, or 15 days of driving.
"Last year we had 12 days and this year we have eight, which means I get four days before the first race, which is not a lot of days. So in that space of time we have to do more mileage than ever before to prove out the car.
"Normally the first day the car breaks down lots and lots of times, but with the advance in technology now the car keeps running. It feels amazing."
Follow live coverage and timing from pre-season testing here
Who is driving when during the first pre-season test
GALLERY: Pre-season testing day two
