Sainz had qualified in third place for the Styrian Grand Prix, although he lost two positions early in the race to Valtteri Bottas and Alexander Albon.
However after that he settled into a secure fifth place and looked to be on his way to pick up solid championship points. That is, until he came in for his pit stop on lap 32.
Carlos Sainz missed out on a higher finish after a pit-stop blunder
Image credit: Getty Images
A problem changing the right rear wheel cost him dearly, and when he emerged from pit lane he found himself down in 13th.
“We want to apologise to Carlos for the issue we had at his first pit-stop, which made his race more difficult than it should’ve been," Seidl said after the finish.
"The delay cost him several track positions and we sent him into heavy traffic, which ruined his tyres and didn’t allow him to fight for the position he deserved to be in today."
“A very disappointing day for me," Sainz himself said. "We missed out on big points after a problem at the pit-stop which meant we came out of the pits in the middle of traffic.
"I had to push too hard too early to try to recover the gap, and that drained my battery and ultimately compromised my tyres for the second part of the race. One of those days when nothing goes your way.