Barely able to lift his head, he glanced over to wife Sophie, whose own eyes carried tears. And he said “I really thought I was going to be world champion.”
It was hard to suppress a lump in the throat at that point.
Here was a man who stood on the cusp of a dream and a life-changing moment.
And Gavin McDonnell gave absolutely everything he had over 36 punishing minutes to grasp that chance.
But the brutal reality of one-on-one sport is that, in the vast majority of cases, there has to be a winner.
Rey Vargas was the man living the dream, clutching the iconic green belt, the WBC world title.
Yet, while many predicted he would steamroller through McDonnell en route to world title glory, he was made to work for it.
McDonnell took Vargas the distance. which only six other fighters had previously done. And he did so with a performance that will have won him plenty of new supporters, despite defeat.
It also brought a round of applause in the press room later in the night – and not every fighter receives such acknowledgement.
It was in that room in the bowels of Hull’s Ice Arena where his disappointment played out.
Seeing McDonnell hunched over afterwards, desperate to leave the building and get back to his hotel, brought two thoughts.
The first was to give him a consolatory pat on the back, tell him well done and hard luck.
The second was to grab him by the shoulders, shake him and tell him to get his chin up after putting in an incredible performance.
Of course, no amount of praise or cajoling for what he produced in the ring would have been enough in that moment to overcome the overwhelming disappointment he felt.
But hopefully, a few days on, McDonnell feels as proud of that performance as he rightly should.
Valiant, heroic, brave. He came of age.
He was cagey in the early rounds, a tactic dictated by Vargas’ fierce power and rapid handspeed.
Commit to offence too soon and McDonnell would have risked being taken apart by the Mexican.
His defences were excellent. Most of what Vargas threw in the first couple of rounds found arms and gloves.
And he managed some smart counterpunching, catching Vargas when at his most vulnerable.
This issue was Vargas was always doing enough to win rounds. Never at a canter but having the edge. He was slick, quick and accurate.
His accuracy only seemed to be on the increase and by the middle rounds it seemed as though he would coast to a dominant, comprehensive victory.
There was never any thought that McDonnell would be stopped though, despite what pundits and bookies predicted in advance.
He was never rocked by a man who had stopped 22 of his previous 28 opponents. Nor did Vargas string enough clubbing shots together in sequence to suggest he could overwhelm McDonnell.
It was just that he could not establish enough control on rounds to tip the balance of the fight.
But his engine never let him down. In fact, it only ramped up as the fight wore on.
Likely driven by the knowledge he had little to lose, McDonnell came on strong in the later rounds, showing renewed aggression and incredible determination.
He forced Vargas back and landed some fine shots over the final four rounds, producing an inspiring finish to a fight most knew he had lost.
Vargas had the comfort of his work earlier in the fight. He knew he had won as much as McDonnell and his corner did.
It was clear enough at the final bell. Vargas received excited hugs while McDonnell got pats on the back.
The announcement of the verdict confirmed it, though there was a brief moment of doubt when British judge Ian John Lewis’ rather baffling 114-114 draw was revealed first. There was little argument to he had with his colleagues’ 117-111 and 116-112 calls which gave Vargas a majority points win.
No world crown was coming back to Doncaster but McDonnell had made history, following twin brother Jamie as the second man from the town to fight for a world title.
There had been plenty of talk of Gavin having an opportunity to step out of his brother’s shadow.
If there was any doubt left heading into the night of whether he was still in the shadows, he stood in the brightest of lights by the end of the fight.
Two stars were born last Saturday night.
Vargas joined the ranks of world champions. And it should be expected he will add further world titles to his haul, and at several different weights at that.
McDonnell inducted himself into the group of fighters everyone loves. Those who never know they are beaten, who leave everything in the ring, who are driven by unwavering heart and determination.
It is for this reason why it is not hard to imagine Saturday night will not be the last time he fights for a world title.
He has plenty to be proud of.