Team Sky leader Chris Froome has admitted he’ll have to do more work on his time trialling before the Tour de France in July, after he lost 37 seconds to rival Richie Porte in a test at the Critérium du Dauphiné.

Porte won the 24km time trial between La Tour-du-Pin and Bourgion-Jalieu this afternoon with a time of 28.07, pushing world time trial champion Tony Martin into second place.

Movistar leader Alejandro Valverde rounded out the podium. Froome was eighth two seconds behind Alberto Contador.

After the stage the Brit took well over an hour to complete his anti-doping duties and had clearly had some time to process the warning signals the result raised for him ahead of July’s big race – which has a similar time trial – and the blow the result had dealt to his campaign for a record fourth Dauphiné title.

“Tough, tough time trial. Not my best performance,” he said. “I think if anything it shows what great shape some of my Tour de France rivals are in [such as] Richie, Valverde did an impressive time trial as well. I knew the level was going to be high coming here, this result just proves it.”

Froome added that he hadn’t had any expectations ahead of the stage and had seen it as an opportunity to test himself against his rivals.

When asked what he had learned ahead of the Tour de France, which features a 23km test against the watch on the penultimate stage, he said: “I’ve still got three weeks now after Dauphiné in terms of TT work, it’s obviously something I’m going to have to do a bit more work on.”

The Sky rider had looked uncomfortable during the TT rolling his body while in he saddle as he pushed up the routes multiple drags. But he was sanguine when speaking to a huddle of journalists, saying: “It’s racing you can’t win all the time.”

Turning his attention back to defending his Dauphiné title, Froome said: “I’ve got my work cut out for me that’s for sure.”

He added: “It does change the dynamic if I’d gained time today I could have ridden more defensively in the climbs, now that I’ve got time to make up it could mean that I could be more offensive over the next few days.”

>>> Tony Martin spotted using prototype Continental tyres and a single ring in Dauphiné time trial

The next few days include substantial mountain stages on Friday, Saturday and Sunday, which will present Froome with the opportunity to claw back time by distancing Porte.

It was not all bad news for Froome he was still ahead of several other GC rivals. He was 23 seconds ahead of Andrew Talansky (Cannondale-Drapac), he was 26 seconds ahead of Simon Yates (Orica-Scott) and 41 seconds up on Fabio Aru (Astana) and Dan Martin (Quick Step Floors).

Frenchman Romain Bardet (AG2R) faired even worse losing 1-53 to Porte and 1-16 to Froome.