The last five kilometre splits have been right on the money at 2:50 each - that's some discipline, and some impressive pace-setting.

Henrik Ingebrigtsen, one of the pacemakers alongside brothers Jakob and Filip, says he is happy to extend his season to be part of this attempt.

"It was like an everyday workout for me and my brothers, trying to stay in formation like we always do," he said.

"Our team did a very good job - the laser jumped a little bit, we were not completely prepared for that but the turn went as smooth as it could have done.

"Being able to participate in an event like this, I feel happy to be part of this."

It looked like a slight trip in the transition from Eliud Kipchoge. They've been pretty smooth so far but the Kenyan had to change his stride slightly as the new pacemakers joined the road that time.

Four-time Tour de France winner and Olympic champion Chris Froome, who was born in Kenya, is watching on in Vienna.

"It's fantastic, just incredible to watch him. It looks like he's not even breathing, just gliding over the road. Hopefully we'll witness history being made today," said Froome.

"Kenya is well known for its marathoner runners but to have someone do something as monumental as this would be such a boost for all the athletes over there, breaking barriers and showing the impossible is doable.

"Especially coming from such humble beginnings, it will inspire people around the world."

And there is still time to get down and make your local Parkrun this morning, although take your phone so you can continue following our coverage...

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Inspired by Eliud Kipchoge's attempts to break the two-hour barrier for the marathon but don't know where to start?

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Former New York City Marathon winner Shalane Flanagan: "It's all about mentally tricking yourself, mental distraction to take yourself out of the moment - I may look forward to something as simple as getting to the next fluid station."

We've hit the hour-mark with 11 seconds to spare. The projected finish time is currently 1:59:48.

There's a fantastic crowd lining the streets of Vienna today too, plenty of cheering and hollering as Kipchoge passes on each lap. They're hyped.

Starmer: It's an interesting experiment, but agree it should not be a world record. Banked corners, and a rotating team of pacemakers, in a fixed formation to maximise slipstreaming, means this is very much assisted.

Claire Hughes: Loving the pacemaker handovers. If this comes off, this *individual* record will go down as the greatest ever team event.

TheMuddyCyclist: If he does this it will be up there with breaking the 4 minute mile. Not convinced he’ll make it, but excited to find out.

He might be the greatest marathoner of all time, but Eliud Kipchoge leads a modest life at his running camp in Kenya's Rift Valley, where he stays with around 30 other athletes.

They set off at dawn for the first of two daily training sessions and spend the rest of the time resting, reading and eating.

"I don't think I am different. I am trying my best to live a modest life," he said.

"I am a simple person, I try to stay calm and focus on what I do. There are no distractions."

Eliud Kipchoge is currently 11 seconds inside his two-hour target after 55 minutes out on the road in Vienna, edging closer to that halfway mark...

Tottenham could do with a new box-to-box midfielder...

Here's Spencer Barden, elite director for the London Marathon, who picked and trained the packemakers: "So far all is going to plan. Early days yet, still a long way to go but the exchanges have gone very well so far.

"We did a lot of work looking at formations, what was best for Eliud and what would give him the best protection. We have a fantastic group of world-class athletes so they are relishing the opportunity.

"They are experienced and know what they're doing. The important thing is not to trip each other and not trip Eliud. We're in a good place."

Eliud Kipchoge is through 15km then, and still on track, wheeling his way around one of the roundabouts at the end of each lap - this course has been designed with slightly steeped banks to help him keep pace and avoid injury before hitting the long straights again.

Eliud Kipchoge first attempted the feat in May 2017 on the Monza National Autodrome racing circuit in Italy, finishing in a time of 2 hours and 25 seconds.

Kipchoge says he is mentally stronger now and he is "confident" that he can get it "the second time".

"My training has been the same, my coach has been the same, my management, everything has been the same. Now the thinking is different," he said.

"I feel more prepared. I feel more ready."

Rob: Asking “will or won’t it be a world record” just belittles the achievement. You can get a world record for eating baked beans with a cocktail stick so this doesn’t deserve to be in that book. It’s amazing. Hopefully he does it in 1:58.

Interesting point, Rob, because my dad once challenged me to eat a jar of pickled onions in world-record time. I managed half, of one...

New York City Marathon winner 2017 Shalane Flanagan: "The pacemakers are looking to be part of something bigger than themselves today...

"The splits are fluctuating but that's nothing to worry about right now. When you begin the race is 10k to go, this is all setting up the stage, the foundation."

The attempt takes place in a huge park where the path has been specially prepared to make it as even as possible.

The surface has been partly retarred and prepared with a banked corner that can save time and avoid injury.

The 42.195-kilometre (26.219-miles) stretch has been prepared so that it should take Kipchoge about 4.5 seconds more than a computer-simulated completely flat and straight course, according to an analysis by sports experts at Vienna University.

Experts say he will only have to descend 26 metres in altitude and climb 12 metres.