Ferrari worked through the night at the Abu Dhabi Grand Prix to help Fernando Alonso in his title battle with Red Bull's Formula One championship leader Sebastian Vettel.
Formula One technical delegate Jo Bauer reported in a statement on Friday that the Italian team had broken a curfew for the first time this season, using up one of their four allowed exceptions.
He said the Ferrari mechanics had been "within the confines of the circuit during the six-hour period which commenced at 0400".
Abu Dhabi is the 18th round of the 20 race season and Alonso is 13 points behind Vettel, who has won the last four grands prix.
The race is the only one on the calendar to run from daylight into the night and the late start means the curfew at Yas Marina runs from 0400 to 1000 local.
Alonso will take part in first practice later after telling reporters on Thursday that he would need three perfect weekends to overhaul his rival and expected everyone in the team to play their part.
"We need to find extra time from every single person in the team, every single mechanic, engineer, driver, pitstop, whatever," the Spaniard said.
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