Marcus Scotney works hard in the heat on day four of the race. Photo: Ian Corless

One of the lead runners in the gruelling Berghaus Dragon’s Back Race is in the ‘last chance saloon’ after being handed his second official warning for deviating from the course.

If Jim Mann receives a third ‘strike’ he will be disqualified from the event on the final day.

The race hotted up both literally and figuratively during the penultimate day, down the Elan Valley and over Drygarn Fawr, a course of 71km (44 miles) with 2,400m (7,875ft) of climbing.

After four days and 252km (157 miles) of mountain running, only minutes separate the leaders in both the men’s and women’s races. In the women’s race, the first three runners are within 15 minutes of each other, while the second-placed man is only eight minutes behind the leader.

Past winner Jim Mann was once again the subject of a rules enquiry after receiving a 15-minute penalty on the first day for missing a checkpoint, and as a result received a second ‘strike’. He went along a path through a farm near the Elan Valley support point, leaving the mandatory route for 200m.

Jim Mann is on his 'final warning'. Photo: Ian Corless

Organisers said: “The race adjudicators looked closely at what happened and concluded that it was a slower route – there were several gates – and no advantage was gained or sought.

“Mann didn’t get a time penalty but the second ‘strike’ means he is on his last warning – if he infringes any rule tomorrow and gets a third strike, he will be disqualified.”

Mann said: “I was just running on auto. I was coming down into a support point and thinking about that and went the way I always go. I just wasn’t looking at the map when I should have been.” He said that he will take extra care on Friday.

Sabrina Verjee still leads the women’s race, but was beaten by both Carol Morgan and Caroline McIlroy on Thursday and her lead is now down to just 6mins 53secs over Morgan. The quickest woman today was McIlroy, who finished in 9hrs 24mins 9secs, which was 11th on the day. Race organisers said the Newfoundland-based Briton is now just over 15 minutes behind the leader and seems to be gaining in strength and confidence as the race goes on.

Unlike many runners, she didn’t seem to be too affected by the heat and is enjoying every minute of her race. “It’s just been a fantastic week,” she said.

With the race being so close there will be a chasing start in the morning. This means Verjee will set off at 8am, Morgan 6mins 53secs later and McIlroy 8mins 18secs after that, the exact time intervals which separate them. The first of the three to cross the finishing line will be the winner, which will make for compelling racing and excitement for everyone following the live tracking online, organisers said.

Sabrina Verjee suffered in the heat on Thursday. Photo: Ian Corless

The men’s race is equally close, but not quite so straightforward, with Marcus Scotney holding a slender advantage after taking the lead on Wednesday. On Thursday, it was defending champion Jim Mann who was quickest, setting a time of 7hrs 3mins 26sec, 56 minutes quicker than he ran on the same day in 2015.

Mann said: “I was all in yesterday and spent at the finish, but I bounce back and went well today.” His impressive run was 18 minutes quicker than race leader Marcus Scotney, who said: “I’m in awe of that run after what happened to him yesterday.”

Scotney finished in 7hrs 21mins 26secs so still holds a lead of just over eight minutes, but he was feeling the heat, and a painful knee. “It was so hot,” he said, “and I’m a bit sunburned as well.” He had started 90 minutes later than Mann, so was in the heat of the day longer, but his main concern was the knee injury. Nonetheless, Scotney has confirmed that he will lead off the chasing start in the men’s race at 8am tomorrow. In third place, Neil Talbott is well over two hours behind the leaders.

Elsewhere in the field, Joe Faulkner is still on course to be the only person to complete all four runnings of the race, while competitors were still working hard to reach the finish before the 11pm cut-off time. Tom Withers was last to cross the line at 10.38pm and will have to recover from his exertions quickly, in time for day five.

The heat and cumulative effect of four days of mountain running continued to wear down the field and several runners needed medical attention after crossing the finishing line. However, the day four campsite offered the welcome sight of a pub within 100m. Many runners took the opportunity to ‘rehydrate’ there.

With one day to go, organisers said there is everything to play for and the 2017 Berghaus Dragon’s Back Race could deliver the event’s most exciting finish to date.

The final day challenges runners with 63km (39 miles) and 2,200m (7,220ft) of climbing, with a significant distance on trackless terrain. The route includes a sting in the tail, with a climb to the summit of Fan Brycheiniog and Carreg yr Ogof on the Black Mountain. It all starts early on Friday morning.

The public can follow the runners’ progress with live tracking on the Berghaus website.