Nico Rosberg's prospects of beating Mercedes team-mate Lewis Hamilton to the 2015 title became slimmer at the Italian Grand Prix after he suffered his first retirement of the season with three laps to go.
Rosberg's weekend was compromised when he had to switch to an old engine prior to qualifying, but he had recovered during the race to run third, before he suffered a failure during the closing stages.
Rosberg has now slipped 53 points behind Hamilton with only seven races remaining this season.
"This weekend was very tough for me," he said. "There were just too many problems with my car which made it impossible to fight for the win.
"It hurts a lot when you have to retire with just two or three laps to go. A few corners earlier, I felt already that I had lost some power but was still hoping I could make it. It was a massive step in the wrong direction for me in the Championship - but to complain doesn't help in these situations.
"I just need to keep pushing and come back even stronger. Giving up is not an option for me. I will push hard to turn things in the right direction - starting in Singapore, which is one of my favourite races."