Problems hit speedy Button
Jenson Button's excitement for the start of the new F1 year proved shortlived, although he still ended the day with a smile on his face.
Just five days ago, at the launch of the new McLaren at the team's Woking headquarters, Button admitted he had never felt so excited ahead of a campaign.
Less than three laps into his maiden run in the MP4-28 on the first day of pre-season testing at the Circuito de Jerez, Button was left cursing as a fuel-pump failure saw him grind to a halt.
It was the same issue that robbed former team-mate Lewis Hamilton of victory in last season's Abu Dhabi Grand Prix when the now Mercedes driver was comfortably leading the way.
The issue resulted in Button twiddling his thumbs for five hours in his motorhome parked inside the paddock as the team attempted to remedy the situation.
Come the conclusion to the day, however, Button was sitting pretty at the top of the timesheet with a lap of one minute 18.861secs.
It was a time that certainly impressed the likes of Red Bull's Mark Webber and Felipe Massa in his Ferrari, who were second and sixth quickest respectively.
To put it into context, throughout the four days of the first test in Jerez a year ago, only three drivers posted quicker times.
However, the cars are an evolution from last year's design, and have effectively enjoyed 12 months of development from those that hit the track last February, so arguably should be quicker.
Regardless, it was still impressive, not that Button was putting any store in it at the end of his 14th opening day of pre-season.
"It's been a very mixed day," said Button.
"With the first day of testing there is so much excitement within the team, but for us the excitement was very shortlived, doing three laps this morning and having the fuel-pump issue.
"It's never what you want at the start of a test, but it's better to have it at the start than at the end so we can solve the issue.
"When I went out this afternoon I was eventually able to do some runs on different tyres to get a feel for the car.
"In terms of that, it's a nice starting point, but not the mileage we obviously hoped for.
"So it wasn't the best. Today wasn't the perfect day with the issues, and there is still a lot of work for us to do before we get this car in a position where we're happy with it.
"As for whether it's a championship-winning car, who knows? The important thing is there is a nice feeling with the car."
As for his time, finishing eight tenths of a second up on Webber, Button initially joked: "I don't know how I did it - I think I cut the chicane at the end."
The 33-year-old added: "I was surprised when I saw the dash, but the time doesn't mean anything.
"Lap times mean nothing right now, and they won't mean anything at the last test.
"It's all about the first race when we will have a very different car then, as every team will, and that's when we need to show how quick we are."
Webber, though, was certainly impressed with Button and McLaren who are not known for grandstanding during testing.
"It was a strong lap time," said Webber.
"I don't know what compound of tyres he was on or what was going on, but it's certainly not a slow lap around here. An 18.8 at Jerez, on Pirellis, is a pretty handy time."
Massa, 1.8secs adrift of Button, also raised his eyebrows at the time as the Brazilian described it as "incredible".
Sandwiched in between Webber and Massa were Lotus' Romain Grosjean, Paul di Resta in his Force India and Toro Rosso's Daniel Ricciardo.
At the foot of the standings, and on his debut as a fully-fledged Formula One driver, was Max Chilton in the new Marussia that was only unveiled at the start of the day.
Unfortunately for Chilton, it is understood a rear suspension failure pitched him into the gravel with only an hour to run when he was at top speed on one part of the track.
"Something gave way," explained Chilton.
"I hadn't hit the brakes at the time. I was still flat out in seventh (gear).
"The team are looking over the car to find a cure. We think we know what it was, but it was one of those things because the testing was going well up until that point."