Danish bad-boy Nicklas Bendtner has fallen offside at VW-sponsored Wolfsburg, and will cop a fine, after breaking club rules by posting a picture of him climbing into a luxury Mercedes.

The picture, posted on social media site Instagram, shows Bendtner climbing into the vehicle with the text: "On my way to another session".

But with Volkswagen being the Bundesliga club's main backer, Wolfsburg bosses have taken a dim view of the Danish forward's decision to use a picture featuring a rival manufacturer's car.

"We have our rules, one of those being that you must pay attention to how you are photographed in public," said Wolfsburg's director of sport Klaus Allofs.

"The rules are not new.

"It's misconduct and it's careless, which at the end of the day will cost (Bendtner) money."

The 28-year-old ex-Arsenal forward has completely fallen out of favour with Wolfsburg's head coach Dieter Hecking and plays second fiddle to Dutch striker Bas Dost and Germany's Max Kruse.

His two-year contract expires in June and, with nine goals in 47 appearances for Wolfsburg, Bendtner is likely to be seeking a new employer at the end of the season.

The Danish bad-boy seems to have curbed the indiscipline (drink driving and other alcohol-related indiscretions) which blighted his nine years at Arsenal, plus loan spells at Birmingham, Juventus and Sunderland, before he joined Wolfsburg in 2014.

After a difficult first season, the 28-year-old scored a late equaliser, then netted in the penalty shoot-out, when Wolfsburg beat Bayern Munich in the German Super Cup last August, but soon found himself back on the bench.

"I've said all there is to say," was Hecking's dismissive reply on Friday when asked about Bendtner, who turned down an offer in January to play in China.

Bendtner was left out of the match squad for Wolfsburg's 3-2 win at Gent on Wednesday in the last 16, first-leg of the Champions League, but is expected to be on the bench for Saturday's Bundesliga match at Hertha Berlin.

Wolfsburg have a mounting injury list with Dost (fractured foot), Diego Benaglio (rib injury), Daniel Caligiuri (bruised thigh), Andre Schuerrle (torn hamstring), Joshua Guilavogui (hip injury) and Sebastian Jung (torn knee ligament) all out.