Mark Webber said the loss of KERS during the Indian GP left him unable to fight Fernando Alonso for second.
The Australian had been running a comfortable second in the early laps, but from one-third race distance said he began to suffer from intermittent KERS issues. In the closing stages, that left him increasingly vulnerable to Ferrari's Alonso, who was ultimately able to coast past on the back straight, and then the McLaren of Lewis Hamilton.
Webber managed to fend the Briton off over the final three laps to hang on to third, but admitted that was little comfort given his pre-race victory ambitions.
Asked about when his KERS issues began, Webber said: "I think it was around lap 19-20, maybe a bit earlier. It was on and off, and then completely off. It was a moving target.
"We needed to screw around with brake balance, and just manage as best we could [to not] lose rhythm and tempo. We needed to keep the focus, but it is so demoralizing on that straight with no KERS – it is not really a battle."
Webber had been able to pull away from Alonso the middle stage of the race, only to once again drop back into the Spaniard's clutches as his KERS gave out. He then came under pressure from Hamilton, but was able to hang on and seal third by just seven tenths of a second.
"I managed to break DRS and get away from Fernando, [when the] KERS there or thereabouts," he related. "Then the blue flags did nothing for backmarkers – the guys don't know how much they kill us in the corners. When I had no KERS, Fernando came past – they [Ferrari] have good top gear – and that was it.
"I pushed as strong as possible to get to the end of the race, but I was lucky Lewis made a mistake on lap 57. That was important because he was starting to get a bit of momentum. I was keen to keep him out of DRS as much as possible.
"I am pretty happy with how I drove but not enough – we could have got more points today for sure."