Sauber team principal Monisha Kaltenborn has leapt to the defence of her driver, Pascal Wehrlein, after the young German was criticised for pulling himself out of the season-opening Australian Grand Prix due to fitness concerns, and labelled claims that he should have battled through the pain barrier as “awful” and “appalling”.

22-year-old Wehrlein pulled himself out of last weekend’s grand prix after battling through Friday’s two practice sessions, with Ferrari test driver Antonio Giovinazzi replacing him for the remainder of Saturday’s and Sunday’s action.

Wehrlein suffered a nasty accident at the Race of Champions exhibition in January in which he rolled a Polaris Slingshot and crashed into the concrete barrier and suffered a back injury that ruled him out of the first pre-season test in Barcelona last month.

After coping with last Friday’s two practice sessions, Wehrlein decided he was not fit enough to race at his full capacity, and elected to give up the seat so that Giovinazzi could give Sauber a chance of achieving a points finish.

“My back is fine but I took a step back in terms of fitness and I’m trying to catch up,” Wehrlein said last Saturday. “I am not feeling like I could do a whole race at my best level.

“Nine weeks ago my injury happened. Then I couldn’t train as hard as I wanted and as I needed to do. I feel like I couldn’t do the whole race distance. If I think after a few laps, ‘That’s painful, I’m losing concentration, I’m losing focus,’ and this would be too high risk.”

But the decision drew criticism from some individuals, one of which was former grand prix winner Mark Webber, who admitted he wasn’t impressed with Wehrlein’s attitude.

“I am not a fan of Wehrlein,” Webber said. “That’s backed up by his soft call saying he wasn’t fit enough. I’m not too disappointed about that change.”

Australian Grand Prix 2017 - in pictures Show all 29 1 /29 Australian Grand Prix 2017 - in pictures Australian Grand Prix 2017 - in pictures Australian Grand Prix Winner Ferrari's German driver Sebastian Vettel (R) and runner-up Mercedes's British driver Lewis Hamilton (L) take part in a press conference after the Formula One Australian Grand Prix in Melbourne Getty Australian Grand Prix 2017 - in pictures Australian Grand Prix Vettel celebrates winning in Melbourne. Getty Australian Grand Prix 2017 - in pictures Australian Grand Prix Vettel clinched the 43rd victory of his career. Getty Australian Grand Prix 2017 - in pictures Australian Grand Prix Hamilton and Vettel embrace after the Grand Prix. Getty Australian Grand Prix 2017 - in pictures Australian Grand Prix Vettel arrives in parc ferme after winning the race. EPA Australian Grand Prix 2017 - in pictures Australian Grand Prix Vettel crosses the line to win the Australian Grand Prix. Getty Australian Grand Prix 2017 - in pictures Australian Grand Prix Fernando Alonso's dogged drive to remain ahead of Nico Hulkenberg and Esteban Ocon was ended after suspected suspension failure Getty Australian Grand Prix 2017 - in pictures Australian Grand Prix Hamilton led Vettel until the pit stops when the Ferrari driver leapfrogged his Mercedes rival. Getty Australian Grand Prix 2017 - in pictures Australian Grand Prix Marcus Ericsson and Kevin Magnussen collide at the third corner in Melbourne Getty Australian Grand Prix 2017 - in pictures Australian Grand Prix Lewis Hamilton led from the start as Sebastian Vettel fended off Valtteri Bottas Getty Australian Grand Prix 2017 - in pictures Saturday Qualifying Sebastian Vettel and Lewis Hamilton speak during the post-qualifying press conference Getty Australian Grand Prix 2017 - in pictures Saturday Qualifying Lewis Hamilton is given a lift down the pit lane in the safety car after clinching pole position Getty Australian Grand Prix 2017 - in pictures Saturday Qualifying Lewis Hamilton claimed pole position for the sixth time in Australia Getty Australian Grand Prix 2017 - in pictures Saturday Qualifying Romain Grosjean locks up a tyre on his final qualifying lap Getty Australian Grand Prix 2017 - in pictures Saturday Third Practice Sebastian Vettel set the fastest lap ever seen around Albert Park to top third practice Getty Australian Grand Prix 2017 - in pictures Saturday Third Practice Marcus Ericsson flashes past the Albert Park Lake Getty Australian Grand Prix 2017 - in pictures Saturday Third Practice Esteban Ocon gets to grips with the Force India car during third practice Getty Australian Grand Prix 2017 - in pictures Friday Second Practice Marcus Ericsson beached his Sauber in the gravel trap during the afternoon session. Getty Australian Grand Prix 2017 - in pictures Friday Second Practice Jolyon Palmer jumps through a gap in the fence after crashing his Renault on the entry to the start/finish straight. Getty Australian Grand Prix 2017 - in pictures Friday Second Practice Palmer's Renault is recovered to the pit lane ahead of a busy night rebuilding it. Getty Australian Grand Prix 2017 - in pictures Friday Second Practice Sebastian Vettel appeared puzzled by the gap to the lead Mercedes of Lewis Hamilton. Getty Australian Grand Prix 2017 - in pictures Friday Second Practice Daniel Ricciardo runs wide on the exit of turn one. Getty Australian Grand Prix 2017 - in pictures Friday Second Practice Romain Grosjean takes a trip over the gravel trap. Getty Australian Grand Prix 2017 - in pictures Friday Second Practice Lewis Hamilton was fastest in the first two practice sessions of the year in Melbourne Getty Australian Grand Prix 2017 - in pictures Friday First Practice The Force India of Esteban Ocon runs over the kerb during first practice. Getty Australian Grand Prix 2017 - in pictures Friday First Practice Daniel Ricciardo flashes by on the back straight in his Red Bull. Getty Australian Grand Prix 2017 - in pictures Friday First Practice Hamilton was half-a-second faster than his nearest challenger in Vettel Getty Australian Grand Prix 2017 - in pictures Friday First Practice Lewis Hamilton pears through his visor at the start of the new season. Getty Australian Grand Prix 2017 - in pictures Friday First Practice Sergio Perez and Esteban Ocon stand by the new pink-livery Force India. Getty

The criticism has not impressed Sauber chief Kaltenborn, who heavily defended Wehrlein and praised him for having the nerve to speak up about his fitness when it would have been easy to stay quiet and put himself in danger.

"He just needs time," Kaltenborn said when speaking to Motorsport.com. "I think it is really awful how people think they have any sort of competence to say anything about him.

Wehrlein completed Friday's two sessions before withdrawing from the weekend (Getty)

"They just have their weird views from wherever they come and have no authority at all to judge over anyone. I think it is rather appalling how people think they can judge this and they should look at themselves first.

"It takes a lot for someone so ambitious to openly admit and say, 'Guys, in these circumstances, I cannot cover the entire race distance'.

Wehrlein was criticised Mark Webber for pulling out of the Australian Grand Prix (Getty)

"So one should rather appreciate that kind of openness and honesty, which is not easy to maintain with the kind of pressure these guys have."