Repeated errors could 'bite' Vettel in 2018 F1 title fight - Wolff

Ferrari driver Vettel lost three grid spots for impeding Carlos Sainz in Austrian Grand Prix qualifying, just a week after his lap one clash with Valtteri Bottas in France.

The stewards noted that Vettel had not been properly kept informed of Sainz's progress by his engineer, but also explained that he had erred by running slowly on the racing line.

"In order to win a championship you need to be as fast as possible, as reliable as possible, and with the least errors," said Wolff. "But sometimes it's very difficult to put all these together.

"I've said it before, Sebastian's biggest strength is his ambition, but sometimes like in Le Castellet it went against him.

"Every team is aware you have to get out of the way in order to not have a penalty, and all drivers are instructed by their engineers about what's happening behind them.

"It's important to try to collect every single point that's there, and when you leave some on the table, that could eventually come and bite you.

"This is the difficulty of being in the car, you need to be aggressive and you need to extract every bit of performance you have, but equally try to avoid the mistakes, and they happen quickly.

"We've had situations, remember Melbourne, where we were just not good enough - we made a mistake and lost the lead.

"So it happened to us as well, and this is going to be how the season is going to go, trying to extract performance and minimise mistakes."

"Kimi's still there," said Wolff.

"The Ferrari is particularly strong on traction out of Turn 3, and into Turn 3 it will be difficult, so the problem is not solved - there is a Ferrari that performs well."

Wolff also highlighted Mercedes' recent power unit and chassis upgrades as key to its upturn in Mercedes form since the Canadian race, which has allowed the team to edge clear of Ferrari.

"Certainly you can see Montreal was also our track in the past, and we weren't able to win the race there, because we lacked performance and the others brought the engine upgrades," he said.

"We couldn't, and this is the one or two tenths that could make all the difference this year.

"In Le Castellet and now we've brought the engine upgrade, we've brought the chassis upgrade, and that's given us a little buffer again.

"That development race is going to continue and you need to bring performance possibly to every race, if you can."