Paffett admits he and Mercedes need to up game during 2014 DTM season

Mercedes was not a factor in the title race last year, as Audi's Mike Rockenfeller defeated the BMWs of Augusto Farfus and reigning champion Bruno Spengler to the title.

Paffett, who took one victory at Lausitz, believes that Mercedes was responsible for its own downfall on too many occasions.

Speaking about his difficult season on the main stage at AUTOSPORT International, Paffett said: "It was a bit surprising, after 2012 which was a fantastic year where we just missed out on the championship.

"There were no regulation changes for 2013, but the first half of the year was quite difficult, and in the second half of the year we were three or four tenths off of the Audis and struggling to score points.

"It was a difficult season, and all of us in the team need to improve. We all made errors.

"I got caught up in incidents at one race that cost us a few points, and then the team made some silly mistakes with strategy and other things that cost us some penalties.

"Overall it was a pretty bad year so we need to improve in every area including the speed of the car."

Paffett added that he believes Mercedes fell behind in the development race in 2013, particularly in comparison to Audi.

"We can probably see where we struggled with the car," he said.

"The upgrades during the year for Audi were mainly around the floor area and the splitter.

"That's where they gained a lot more downforce than us and that's where they found the pace.

"We just need to make sure we are 100 per cent focused and doing the best job we can because last year we did far from the best job."