Lewis Hamilton is dealing with the poor start in his attempt to claim a third consecutive title like a "true champion", according to Mercedes boss Toto Wolff.

The Briton has struggled due to reliability issues, poor starts and contact with other drivers during the opening three rounds of the F1 season and has yet to trouble team-mate Nico Rosberg, who has sealed an impressive hat-trick of victories.

Rosberg is already 36 points clear in the Drivers' Championship ahead of this weekend's Russian GP but Hamilton, who admits he is "out of jokers" in 2016, has kept calm thus far with 18 races remaining.

And Wolff says that he is impressed by the way both Mercedes drivers have handled their contrasting starts to the campaign, noting the adversity Hamilton has faced.

"Both drivers are in a good place mentally," the Mercedes head of motorsport said. "Nico is on great form but keeping his feet firmly on the ground.

"Lewis would have every right to feel disheartened by his start to the season - but he is calm and confident, handling adversity like a true champion."

Hamilton had to start the Chinese GP from the back of the grid due to a power unit failure in qualifying and Mercedes have confirmed that the MGU-H has now been repaired, with an insulation error thought to be the problem, and the unit will travel to Russia as a spare.

Sky Sports F1’s Natalie Pinkham joined Lewis Hamilton for a live Facebook chat following his return from the Chinese GP Sky Sports F1’s Natalie Pinkham joined Lewis Hamilton for a live Facebook chat following his return from the Chinese GP

The Sochi Autodrom has been a happy hunting ground for Hamilton, however, winning both of the previous grands prix at the venue, and he remains confident that his season will soon start to improve.

He said: "There was plenty going through my head after China, as you'd expect. But, after all these years, experience has taught me to stay calm and keep pushing forwards when I get knocked back. I've been here before a few times now.

"A lot can happen over the next 18 race weekends and I have the utmost confidence in this team. But adversity is part of the journey: it brings us closer, makes us stronger and I know that together we'll bounce back, so I'm confident of better weekends to come.

"There are lots of positives to carry into the next battle. If nothing else, I know after these first few races that I can still overtake!"

Rosberg extended his winning streak to six in Shanghai but as well as fearing a comeback from his team-mate, he also believes Ferrari and Red Bull are hot on the Silver Arrows' tail.

"I would never have expected the first three weekends to go the way they have," he added. "I've made the most of my opportunities and I have a bit of an advantage in the points right now - but we are only three races down and it would just take one bad weekend for that gap to disappear.

Most consecutive F1 wins

"Lewis is still the benchmark for me as he is the current champion, Ferrari haven't shown what they can do yet and Red Bull also look like they're getting stronger, so it's going to be a good battle and I'm looking forward to that. I wouldn't have it any other way."

Don't miss the F1 Report on Wednesday at 8:30pm on Sky Sports F1 for a preview of the Russian Grand Prix. Natalie Pinkham is joined in the studio by Marc Priestley and Dominic Harlow.