Former Formula 1 driver Mark Webber has questioned the performances, strategy, and attitude of Sebastian Vettel in the 2018 drivers' championship battle with Lewis Hamilton, and wonders whether the poor results for the German will result in him starting to "feel the heat" at Ferrari.
Hamilton was poised to claim his fifth world championship during the United States Grand Prix at the Circuit of the Americas on Sunday - a circuit which has proved to be a happy hunting ground for him in the past.
The Brit needed to better Vettel by eights points in order to win the title, but could only manage a third-place finish - one ahead of his rival.
Vettel's championship assault has crumbled since the summer break, with a flurry of mistakes, and indeed problems with Ferrari strategy, allowing Hamilton and Mercedes to steadily extend their lead in both rankings.
Webber, a former team-mate of Vettel at Red Bull, reckons the four-time world champion has been "average" in the second half of the season.
"He shouldn't be in this position." Webber told Channel 4 following the US GP.
"Red flag, he went too quick in practice so there's a penalty. Suzuka - stuffed up the tyre situation when it was wet. You've got to be proactive, you've got to be on the offence, not on the defence all the time.
"He's driving for Ferrari, it's not like he's mid-pack trying to pull a few fluky results together. This is a serious world championship campaign. He's been flaky. Since the summer break, he's been average.
"What's he going through, Seb? He's human, but at Maranello is he starting to feel the heat? Arrivabene is an interesting cat to say the least, how's he managing his driver? He doesn't manage us too well."