Formula One drivers welcomed wider grid slots from Sunday's Australian Grand Prix after Esteban Ocon and Fernando Alonso were penalised for missing their marks in the season's first two races.
A spokesman for the governing FIA said on Thursday that the boxes would be 20cm wider for the race at Melbourne's Albert Park circuit.
A central guideline will also be trialled on Friday to see whether that helps drivers align their cars correctly on the starting grid.
The grid positions were already enlarged by 20cm at the start of the season compared to last, with drivers struggling to see the markings after the sport switched to larger 18-inch wheels in 2022.
Both Alpine driver Ocon and Aston Martin's Alonso, the most experienced driver in Formula One history with a record 357 starts, were handed five second penalties for the breaches in Bahrain and Saudi Arabia respectively.
Double world champion Alonso doubted the central line would make much of a difference.
"You approach the box looking sideways, so you're not looking forward, so that's the biggest difficulty," he told reporters. "But the 20cm will help I guess.
"There's going to be some circuits, maybe Monaco, or Imola that you start a little bit sideways anyway. Because if not you crash if you start there straight. So, we'll have to see how we apply the penalties and things like that in those races."
"But no one wants to get a penalty for the start. Also, I think the FIA doesn't want to have any problem with that, because there is no performance advantage, as long as you don't go too forward. Hopefully we avoid anything from now on."
Other drivers agreed the wider slots were necessary.
Mercedes' George Russell, a director of the Grand Prix Drivers' Association, said a five-second penalty for being laterally out of place was "probably too harsh".
"We can't see anything when we line up so the penalty needs to be reflected on the difficulty," he said.
Alpine's Pierre Gasly said lining up correctly was "one of the most stressful times of the race".
AlphaTauri's Dutch rookie Nyck de Vries agreed.
"You literally can't see anything...you kind of reference yourself to the car in front of you and then you kind of guess where you are," he said.