The race dubbed Britain’s most brutal was heading for a close finish as the three leading competitors entered the final few hours within minutes of each other.
As midnight approached, Tom Hollins had taken the lead shortly before the runners reached the Border Ridge in the Montane Spine Race.
Close behind him were Pavel Paloncý and Eugeni Roselló Solé, who were overtaken by the Yorkshire anaesthetist who caught up with the pair who had led the race for most of its distance.
Last year’s winner Eoin Keith dropped out of the race on Wednesday with a suspected fractured rib. He had not been on top form since a fall early in the event, on to his chest-mounted GPS unit.
As the front three approached Byrness, Hollins’s lead was about a kilometre over the Czech and the Spaniard, both past winners of the Spine Race.
In the women’s race, Irish runner Carol Morgan further extended her lead over Helene Dumais of Canada during Wednesday, leading her by more than 50km. Third place was being contested by Sarah Fuller, Gabriele Kenenberg and Yvonne Lehnert.
After leaving the checkpoint at Alston, 180 miles into the 268-mile race about 10pm on Tuesday, 2014 and 2015 race winner Pavel Paloncý was in first place, while 2013 winner Eugeni Roselló Solé left the checkpoint just 24 minutes after him.
They battled each other for most of the day, as the two traversed Hadrian’s Wall before turning north again towards the Scottish Borders. After neither could gain an advantage, the regular Spine rivals agreed to run together to the fifth and final checkpoint in Bellingham, 43 miles from the finish in Kirk Yetholm.
In Bellingham the two runners, who have battled each other for podium spots in the 2014, 2015 and 2016 Spine Races, rested for about three hours.
As they slept, Hollins, who won the 108-mile Montane Spine Challenger in 2016, grew ever closer. And as Paloncý and Roselló Solé left Bellingham, Hollins caught up with them.
Montane Spine Race organisers said: “Recently Hollins has looked like the freshest of the three.
“Unlike the other two, he is a supported runner, meaning a crew can meet him with a campervan whenever the trail crosses a road, an option open to all Spine Race competitors. Hollins aims to finish in under 100 hours. The course record is 95hrs 17mins.”
The three will race through Wednesday night across the remote Cheviot Hills in the Scottish Borders to Kirk Yetholm. The first runner is expected to finish about 8am on Thursday.
There have been 36 retirements so far from the race, which follows the Pennine Way from its southern start in Edale, Derbyshire, to Kirk Yetholm in Scotland.