Both Michael Schumacher’s former team Mercedes and the current Formula One world champion have sent messages of support to the German great as he continues in coma a month after a skiing accident.

Mercedes included a message for Schumacher on the side of its new Formula One car, while four-time defending champion Sebastian Vettel said he was praying for his friend and countryman.

Drivers Lewis Hamilton and Nico Rosberg unveiled Mercedes’ silver-and-turquoise W05 before the first session of the pre-season began at the Jerez track.

The upper part of its chassis just behind the driver’s seat carries the Twitter hashtag (hash)KeepFightingMichael.

Rosberg was Schumacher’s teammate for three seasons before the seven-time world champion retired from F1 for a second time at the end of 2012.

Vettel, who drives for rival Red Bull, says that he “was as shocked as anyone else in the paddock”.

“I have known him for a long time and have been looking up to him all my life,” said Vettel.

“I got to know him obviously when he did his comeback a little bit more and became his friend.

“It’s horrible, especially for his family and close friends not knowing what’s going to happen.

“I pray and hope a miracle will happen and he will come back and be the person he has always been before.”

Schumacher suffered severe head injuries while skiing in the French Alps on December 29 and has been in an induced coma since. He remains in a stable condition.

Pre-season testing continues in southern Spain until Friday.

The next tests will be held in Bahrain on February 19-22 and February 27-March 2.

The season opens with the Australian Grand Prix on March 16.