Kieran Wallace substitution explained after ex-Nottingham Forest midfielder's early Hartlepool United withdrawal

Wallace was a surprise substitution after just half an hour of Hartlepool’s National League fixture at Marsh Lane with the midfielder, seemingly, untroubled by an injury during his exit from the field.

Given the extreme conditions there were suggestions the 28-year-old may have been struggling with the heat, but manager Askey confirmed the midfielder had been dealing with an illness and was unable to continue.

Askey said: “He was ill. The longer the game went on he was just getting worse and worse and he just couldn’t continue, so it wasn’t an injury.”

Wallace’s exit appeared to disrupt Hartlepool’s control of the game as the hosts soon drew level through Olly Sanderson.

But Wallace wasn’t the only player dealing with an issue, with defender Emmanuel Onariase struggling with his fitness.

The defender suffered an untimely slip in the second half which allowed Pierre Fonkeu a clear run on goal to add a fourth for Oxford and take the game away from Pools.

And Askey admitted after the game the defender would not have played had there been other options available – with Alex Lacey not 100 per cent either following his return to training.

“Mani, under normal circumstances, wouldn’t have played today, but the longer the game went on you could see he was struggling," said Askey.

“We’d already made a substitute because we were trying our best for another goal.

“It’s his groin and his knee, and playing on pitch like that took its toll as the game went on.”