Lewis Hamilton's Mercedes team will analyse why their world championship-winning driver has suffered a recent drop in performance, Toto Wolff has said.
Hamilton won his third world title with three races to spare in last month's United States Grand Prix, but has subsequently finished second to Nico Rosberg at the ensuing rounds in Mexico, Brazil and the season-ending race in Abu Dhabi on Sunday.
The British driver also secured pole position at 11 of the opening 12 races, but has not started from the front of the grid since September's Italian Grand Prix - a streak which now stands at seven races.
In contrast, his Mercedes team-mate Rosberg has recorded six poles on the spin and secured a hat-trick of consecutive victories for the first time in his grand prix career on Sunday.
"There has been so much discussion about whether he (Rosberg) has stepped up his game, has the car come towards him, or whether Lewis has taken it more easy," Wolff, the Mercedes boss, said.
"I think we have to do an intelligent list over the next couple of weeks and try to analyse why. He is still pushing very hard. He is still the same guy with the same talent and putting the same effort into it."
Hamilton has been untouchable for much of the campaign, but he admitted his dip in results are a concern heading into next season.
Speaking after qualifying on Saturday, Hamilton said: "I was just sitting with my engineer and I said 'we really need to sit down and try to figure out how we are going to rectify this'.
"I have got this great graph which shows you all the races, and all 12 of the opening races - apart from Barcelona - the car was great. Since then it has been terrible - terrible laps, terrible balance, particularly (on Saturday) - so I need to figure that out.
"While it looks like one side has gone a lot better, essentially from our point of view as a team, it's quite the opposite, I've got worse."
Mercedes were mysteriously off the pace at the Singapore Grand Prix, and Hamilton has said he's felt uncomfortable with the balance of the car since.
Wolff added: "After Singapore we developed in a different direction and whether the car has come more towards Nico and gone away from Lewis, I don't know.
"It could be a factor, but I wouldn't want to reduce it to one single factor. It could be many possible factors."
Source: PA
