A year ago Sebastian Vettel headed to the Belgian Grand Prix and would proceed to win nine straight races en route to his fourth world championship.
Fast forward to now and very few would have predicted how the Red Bull driver's fortunes have changed.
Certain to lose his 'number one' status to either Lewis Hamilton or Nico Rosberg, Vettel is now arguably not even the best driver in his own team as Daniel Ricciardo takes the F1 world by storm in a remarkable 2014 season.
The raft of rule changes has seen the demands on the driver not suit the man who had become the master of the 'blown diffuser' era as Vettel struggles to get the most from his RB10.
Fall of a champion
It was always known that replicating the same dominance of the past few years in 2014 would be near impossible given the new focus on power units and the restrictions on aerodynamics, also, current pacesetters Mercedes have been building towards the change to V6 engines ever since they returned in 2010.
But the distance Sebastian Vettel has fallen off his perch since last year is what has surprised the most.
Here was a driver who was phenomenal in the Toro Rosso in 2008 - winning in the rain at Monza - yet in a car with the same lack of downforce and aerodynamic aids, Vettel has been unable to get close to the form that could see him match some of Michael Schumacher's most incredible records and instead made him look rather feeble compared to the giant he was in recent years.
His seemingly rapid fall from grace hasn't been all his own fault however, whereas it was always Mark Webber who appeared to get the bulk of unreliability, instead it has been Vettel enduring the rough end of the stick when it comes to mechanical problems, not that Ricciardo's season has been completely trouble-free.
The German has had three retirements so far as well as having to fight through the field at other races.
Currently he lies a lowly sixth in the Drivers' championship with a best of third, which he has achieved twice so far this season.
What's next for Seb?
With the emergence of Daniel Ricciardo and the arrival of Mercedes as the team to beat, the question has to be asked what is next for Sebastian Vettel?
Next year may see another change in the pecking order as the Renault power unit, that has been such an Achilles heel to the team in 2014, can be upgraded and, for Red Bull at least, hopefully close the gap to the leading Silver Arrows.
For Vettel he will be hoping for a much better Winter testing, another factor in Vettel's struggles to adapt in 2014, so that he will be in a stronger position heading into the new season and therefore put up a better challenge to team-mate Ricciardo.
Red Bull future
If Red Bull don't manage to close the gap to Mercedes in the coming year, however, or if Ricciardo continues to be 'top dog' at the team, then questions over his future with the team and company that helped nurture him into the champion he is, may start to rise.
Already, as part of the accustom 'silly season', speculation has linked Vettel to Mercedes and there has been the long held belief that a stint with Ferrari would be a part of the German's career.
Certainly with so many young Red Bull academy drivers showing incredible potential, if Ricciardo maintains his form then maybe an 'ageing' Vettel could be the one to make way for the likes of Daniil Kvyat, an incredible thought but perhaps not a farfetched one.
Has Vettel peaked?
The question I posed in the title to this article is an interesting one, after four years of incredible success it is highly unlikely a new style of F1 would see the man who led it so convincingly 12 months ago suddenly lose his ability to win.
So while I believe that no, Sebastian Vettel has not achieved all that he will in Formula 1, the reasons stated above highlight that he will have to re-find some of his form from the past few years if he is to be given the chance to enhance his F1 achievements beyond their current standard.