Citroen's Yvan Muller says he doesn't feel as if he's achieved anything special during his record-breaking WTCC career, and that he was just 'doing his job'.
The Frenchman joined the series in 2006 and remains the most successful WTCC driver of all time with four world titles and 48 wins.
The 47-year-old Citroen driver is currently fighting for second place in the championship and has confirmed his departure from the series after 2016.
"I've been racing in this series for 11 years. If you want to keep a certain level, you need to perform 100 per cent constantly to stay there", the Frenchman told Motorsport.com.
"I can feel that I don't have the same motivation anymore, and the urge to make the necessary effort to stay on top might not be there anymore."
"After so many years, I want to do other things. That's why I have decided to leave WTCC."
Muller notched up his first career win in the third round of his first season in the Seat Leon, ending fourth overall.
The French driver went on to win his first world title in 2008 with Seat.
Nothing exceptional, "just my job"
Joining Chevrolet in 2010, Muller won back-to-back titles despite tough competition from teammate Rob Huff.
In 2013, when Chevrolet put an end to its official involvement in WTCC, the RML team lost the American constructor's support, which didn't stop Muller from winning his fourth title, likely the last one.
He is the only driver ever crowned with an independent team in the history of the series, as well as the only driver ever crowned with different constructors.
The Frenchman got involved in Citroen's WTCC programme with Sebastien Loeb in 2014 and finished runner-up to teammate Jose Maria Lopez in 2014 and 2015.
Since 2007, Muller has always finished on the podium of the championship. He's also the record-holder for most wins – 48 in his career.
"I don't feel like I've achieved something exceptional", he said. "I've just done my job."
However, Muller is not retiring as a driver. He wants to take time to think about his future in motorsport.
"For the first time in my career, I don't have a plan for next year", he adds. "But I find it interesting because I'm opening to other things, from a sporting point of view but also outside sports."
Elsewhere, Muller created his own race team, Yvan Muller Racing, three years ago, with titles in Mitjet 2L 2014) and the French Supertouring Championship (2015), both with young driver Yann Ehrlacher.
In 2016, YMR joined European Le Mans Series with a Ligier JS P3 driven by Alexander Cougnaud, Yann Ehrlacher and Thomas Laurent.
Last June, Cougnaud and Laurent won the Road to Le Mans race, a curtain-raiser for the 24 Hours of Le Mans, driving a Ligier JS P3 entered jointly by Yvan Muller Racing and DC Racing.
"I don't want to quit racing completely, but it will only be one-offs, according to what I want, just for fun. For now, I'm stopping WTCC and I don't want to plan anything next."
"I want to develop other activities and get involved in projects for which I have been lacking time. My team, Yvan Muller Racing, but also activities outside competition, including coaching amateur drivers, be they complete rookies or experienced drivers."
"For the time being, I'm still a professional driver and my priority remains the last two rounds of WTCC in Shanghai and Qatar.
"Aiming for second place in the championship. Fighting for second place is not most satisfying, but that's how it is. I'll do my best to achieve this goal."
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