Nico Rosberg's title chances may have suffered a massive blow in Monza following the German driver's late retirement from the Italian Grand Prix.
Rosberg was closing on Vettel for second place when his engine expired on lap 51, eliminating the second Mercedes on the spot.
While the German camp nervously awaits the result of the FIA's investigation into an alleged technical infringement involving illegal tyre temperatures - and a potential disqualification - Rosberg's deficit over Lewis Hamilton in the driver's standings now stands at 53 points.
"It's all very disappointing, for sure" commented a chagrined Rosberg. "The whole weekend just went wrong completely, just very unlucky."
"So many repercussions of this engine issue, which was actually a chassis issue that made have to change engines. it was a difficult race as a result. To have it explode two laps from the end is even more disappointing."
Rosberg's untimely demise occurred just as the German was preparing to mount a final attack on Vettel, with the second place on the podium at stake.
"I was going to have a good go at Vettel, as the brakes had cooled enough to be able to attack and I could have ramped up the ERS power a bit."
Should the provisional results of the Italian Grand Prix be confirmed, it would naturally be a severe set-back to Nico Rosberg's title hopes.
"It's a fact that today was a massive step in the wrong direction," lamented the Mercedes driver. "Just when I needed to catch up a few points, it's been the biggest loss in one day that I've had in the season. But there's no giving up and I'll just keep fighting, and try to win the next couple of races somehow."
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