GERAINT Thomas will be a tough nut to crack in the battle for the Yellow Jersey.

So says a Conwy cycling figure as the potential of a first Welsh Tour de France winner draws closer.

Should current leader Geraint Thomas get through today's stage 19 unscathed, he will be a near certainty to wear the Yellow Jersey all the way to Paris on Sunday.

However, what a day it is!

The peloton is tasked with ascending the Col d'Aspin, the fierce Col du Tourmalet and Col d'Aubisque before the end of the 200km stage.

At present, Thomas holds a comfortable lead of one minute and 59 seconds over second-placed Tom Dumoulin.

Thomas' Team Sky team-mate Chris Froome is a further 33 seconds back in third place, just ahead of Primoz Roglic.

However, an attack from Movistar rider Mikel Landa over the Tourmalet means he would be in third position if the stage stopped now.

Rhos on Sea Cycling Club secretary John Clayton said: "I expect the whole of Sky to work together to support Geraint. Chris Froome will also support Geraint.

"If there's a breakaway, then Sky will let it go unless there's another GC (General Classification) rider in the break.

"Dumoulin has the best chance of clawing time back on the time trial rather than today, unless his team can work a miracle.

"Dumoulin will need to keep something in the tank for the TT, which is the best chance, but Geraint will be tough to crack.

"Without a mechanical or accident, G will be the first Welsh winner of the Tour.

"(It's) long overdue for him and (it would be) well deserved.

"David Brailsford is an honorary member of Rhos on Sea Cycle Club and has competed in our own club events, so there is a strong local connection.

"We are all behind him."

Rhyl Cycling Club secretary Jon Harland said: "There will be fireworks from Dumoulin and Roglic.

"They will need to gain more time ahead of tomorrow's time trial as Geraint Thomas is too far ahead overall to be caught on just that.

"I expect him and his team to successfully mark all rivals.

"The only issues for me are is Thomas going to suffer a 'bad day' or will the terrain, particularly the descending, cause problems for him?"