Sebastian Vettel said he was relieved to take victory in the Spanish Grand Prix after being pushed hard by McLaren rival Lewis Hamilton.
The Red Bull driver crossed the finish line just six tenths ahead of the Briton, after fending off his attacks for several laps despite not having KERS working properly. Vettel, who took his fourth win in fives races, admitted it had been a very difficult race.
"It was pretty tough, obviously," said Vettel. "It was really close, thankfully in last two laps I got quite a good run in the last sector and it was enough to make it stick. On top of that we had sometimes KERS on and sometimes off, so not an easy race, and McLaren and Lewis gave us a very, very hard time.
"But it is a big relief when open to the main straight and there is checkered flag. I am very happy, a great result and a confirmation we are very strong but surely today was not as not expected by many people. We saw Ferrari there and McLaren gave us a hard time. That is why I am more happy, as we made it with these guys pushing so hard."
The World Champion, now leading Hamilton in the standings by 41 points, insisted Red Bull must fix its issues with KERS, especially with rival closing the gap.
"When they told me with six laps to the end not to use KERS, it wasn't best message I was hoping for. I don't have to say it here – they know that it has to work in the future. It is absolutely necessary. So after the loss of KERS, surely we are not yet were we want to be."