Eliud Kipchoge's sub-two hour marathon underway in Vienna

The INEOS 1:59 Challenge, where Eliud Kipchoge is seeking to become the first man to run the marathon under two hours, is currently underway at the Prater Park in Vienna, Austria.

Kipchoge, is being assisted by a group of seven pacesetters in the first phase among them former Olympic champion Bernard Lagat.

Five athletes are running in front of Kipchoge while two are behind him with Kipchoge sandwiched between the pack. This 'V' formation is according to plans by the organisers to maintain the pace and protect Kipchoge from wind.

Ahead of the pack is a zero-emission Audi E-tron car, the latest from the German manufacturer in the electric car market, which is beaming green laser lights onto the tarmac to guide the runners to stick to the pace agreed on, which is two minutes and 50 seconds per kilometre.

Just to make sure the car’s pace is spot-on, the driver has been asked to use the cruise control facility that will ensure the steady pace. Each runner will have a chip fitted in his shoe, and with car’s cruise control not 100 perfect efficient, organisers have thrown in transponders at every kilometre to ensure the correct pace is maintained, with a back-up car at the ready, just in case.

According to the race organisers, Kipchoge is within target after a good pace in the opening five kilometres.

"That’s the first 5km down for @EliudKipchoge and so far, so good. For what it’s worth at this stage, his time of 14:10 means a projected time of 01:59:50," read a tweet from INEOS 1:59 Challenge.

After the first 10km, Kipchoge is doing better than his first attempt in 2017 in Monza, Italy.

"For context, @EliudKipchoge ran that first 10km in 28:20. That’s one second quicker than his 2017 sub two-hour marathon attempt in Monza. 5km - 14:10, 10km - 28:20 (+14:10)," confirmed INEOS 1:59 Challenge on Twitter.

A remarkable 42:34 was Kipchoge's time at the 15km mark.

"There’s no runner better to watch than @EliudKipchoge in this kind of form. The crowds in Vienna are roaring him on and he’s just passed the 15km mark in a time of 42:34," tweeted INEOS 1:59 Challenge.

After 20km, almost halfway through, Kipchoge is still within the targeted time.

"We’re nearly at the halfway mark and still no sign of strain from @EliudKipchoge. He looks calm and focussed despite averaging a speed of over 21km/hour. The current projected time is 01:59:51," tweeted INEOS 1:59 Challenge.

With 17km left, organisers are confident that Kipchoge can reach the target 1:59 though there should be no errors.

"There’s absolutely no room for error here as@EliudKipchogecontinues to hit his marks with military precision. He reaches 25km at 01:10:59 but one mistake could change everything," tweeted INEOS 1:59 Challenge.