While Sebastian Vettel looks set to continue his march to the drivers' title after taking pole position for today's Indian Grand Prix, the Scot will line up 16th on the grid, his second-worst performance in qualifying in 46 F1 races.
There has been a clear disparity between Di Resta and team-mate Nico Hulkenberg at the Buddh International Circuit, with the German, who starts 12th, consistently quicker and qualifying 0.7 seconds faster.
"I can't get any consistency or confidence in the car. I've never felt it as nervous as that," said Di Resta at the end of a week in which he has had to accept there will be no move to one of the big three – McLaren, Mercedes or Ferrari – for him next season.
"You never see that much of a difference between me and Nico. It's always 10ths [of a second], but here I can't get close to him. There are indications there is something not quite right with the car. I can feel it in the car itself.
"Yesterday we put it down to issues with a puncture, but it's clear it's more serious than that. It resulted in the hardest qualifying session I've had to contend with in Formula One.
"We need to get on top of things, to understand what the actual issue is to rectify it. We're looking at it, with the data showing signs of some things we can pick up on."
Despite the problems, Di Resta refused to rule out the possibility of a top-10 finish, adding: "It's going to be damage limitation, but I'm not going to give up on it.
"We're reasonably hopeful we can try to do something, and we'll certainly put the pressure on for that to happen."
The next race, in Abu Dhabi, is only a week away but Di Resta is convinced his car will be fixed by then. "There won't be a repeat of this in Abu Dhabi, that's for sure," he said.
"The focus [today] is to try to see what we can do, and there are things we need to make sure are right with the car. Beyond that I believe there is enough time for us to get to the bottom of things before Abu Dhabi. I would think there will be a massive investigation on it."
Vettel, who won from pole in the inaugural Indian race last year, was part of a third successive one-two sweep for Red Bull, with team-mate Mark Webber once again lining up alongside him. Behind them are the McLaren pair of Lewis Hamilton and Jenson Button, with the third row occupied by the Ferraris of Fernando Alonso – Vettel's closest challenger – and Felipe Massa.
Hamilton insisted he and Button will be in contention for a win, saying: "We weren't quick enough to be ahead of these guys, but we can definitely challenge them in the race. Our race pace is just as good as theirs."
Alonso refused to be downcast about his place on the grid or concede that his title hopes are ebbing away. The Spaniard said: "I think it's more challenging for us now but I remain 100% confident we will fight for this championship and we will win it."