Last year was truly terrible for McLaren. So bad that Fernando Alonso skipped the Monaco Grand Prix to drive in the Indy 500. So bad that the team ended a factory engine agreement with Honda to become customers with Renault in the hope of gaining reliability and pace.
The first test of 2018 was promising, though much of it was held in sub-par weather conditions. The second test of the year kicked off today, and McLaren's MCL33 broke down three times and was classified 12th quickest of the 13 runners.
Stoffel Vandoorne was driving today when the car " in the morning session and a hydraulics issue after the lunch break." It's also possible that the bodywork was overheating and too close to the exhaust.
That's not at all what McLaren wants from testing, but the team seems unfazed. Racing director Eric Boullier has said that and that there's "no drama" within the team because of the bad day.
To be fair, it wasn't a great day for a few teams, with Verstappen's Red Bull stopping on track in the afternoon, a brake issue for Toro Rosso, and undisclosed issues for Haas keeping them in the garage.