LE PUY-EN-VELAY, France — Staying calm is what helped Chris Froome and Sky save the yellow jersey on a dramatic day at the Tour de France on Sunday, his Spanish team-mate Mikel Landa said.

Froome suffered a mechanical problem 50km from the end of the 189.5km 15th stage from Laissac-Severac l’Eglise to Le Puy en Velay that saw him drop 50 seconds behind his main rivals at one point.

But after a mad 20km chase, he latched back onto the group ahead, with Landa, who had stayed alongside the other favourites, dropping back at the last moment to help Froome bridge up after Sergio Henao and Mikel Nieve had provided most of the chase effort.

"I just stayed in the first group, and when he was closer, I waited a little bit and we came back together," said Landa, who dropped a place from fifth to sixth overall at the finish after a late attack by Dan Martin.

"I was in the first group, so I always let them (the team) know how things were going. We stayed calm and saved the day very well."

Landa’s role in Sky has been under scrutiny these last few days with rumours all is not well and suggestions the Basque rider might be a loose cannon.

He was seen being berated by Sky sports director Nicolas Portal following Thursday’s 12th stage in the Pyrenees after Froome had cracked on the short, steep, final climb to the finish.

Rather than stay with his team leader, Landa accelerated away to try to win the stage.

The very next day he joined Alberto Contador in a breakaway and gained almost two minutes on his own team leader by the finish, moving up to fifth overall, just over minute back.

Sky and Froome insisted it had been a good move to give the team "a great card to play" and a "plan B".

But not everyone is convinced.

Irishman Stephen Roche, the Tour winner in 1987, said he thought Landa was the biggest threat to Froome winning a fourth title.

"We don’t know if the strategy of Sky the other day was purposely to let Landa up the road to have a plan B, or was it because of some internal discussions we’ll never know about?" he said.

Panic stations Landa is rumoured to be leaving Sky next year as he is unhappy at being a domestique for Froome and wants to try to win Grand Tours himself.

But Froome made a point of thanking him for coming back from the favourites’ group to help his leader.

Froome suffered a mechanical problem due to a broken spoke in his back wheel and found himself distanced as he had to stop and change a wheel with team-mate Michal Kwiatkowski.

"That was extremely stressful, panic stations really. I thought that could be the yellow jersey changing shoulders again after this stage," said Froome.

"I’m just grateful I was able to get back to that front group because it was a critical moment of the race.

"It’s thanks to my team-mates for dropping out of that front group and helping me to get back, especially Mikel Landa who dropped out of the front group in the last kilometre there to help me get back."  — AFP