James Cracknell anticipates a heavy bump back down to "real life" after becoming the oldest-ever Boat Race winner aged 46.
The double Olympic gold medal winner powered Cambridge to a third win in four years in the 165th Boat Race, then conceded the void that follows will prove "empty".
Cracknell suffered a traumatic brain injury in 2010 when fracturing his skull in a cycling accident in Arizona only to battle back to full health, while just last week he confirmed the end of his marriage to Beverley Turner.
Cracknell's former Olympics crew mate Matthew Pinsent believes no one will ever match this feat, though warned his old friend to beware the nagging question of what comes next.
"This last two weeks has been something I've had to focus on," said Cracknell.
"To be honest, tomorrow's going to be hard, it's going to be empty. And that's when real life starts."
Eight years older than the previous record holder, Cambridge's 1992 cox Andy Probert, Cracknell produced a stunning feat that Pinsent believes will remain forever unmatched.
"This defies explanation, it is an outstanding achievement," said Pinsent.
"In the history of the Boat Race, no one will ever do that again; absolutely no way.
"In that hospital in Phoenix, if you'd said he would win the Boat Race, at that point he was doing well to walk again.
"What more can you do? Rowing across the Atlantic, that's no longer good enough now.
"Going to the South Pole's old hat. The Marathon Des Sables? He's been there, done that.
"So what is there to do? And that will be a big question for him.
"This time last year he was running the London Marathon at 2hrs 43 and his weight then was in the low-80 kilos.
"Then he went on (TV show) The Island and dropped down to the 70s.
"With all his physical attributes intact, with six months to go at 46, that would be a mountain to climb. But he was coming in 15 kilos out of rowing shape.
"And that stuff you can't put back in six months. I think he's already said this is one of his greatest achievements. It will certainly feel like that tonight.
"But tomorrow morning, for every Boat Race competitor, the Monday morning is a real clunk.
"Everyone who competes in this, the next day thinks: 'now that's out of the way, what on Earth am I going to do now?'
"And that will be many times over for James.
"Because he's poured his life and soul into it, and it's been that much harder for him at his stage of life, with all the commitments and sacrifices he's made."
Cambridge won the Women's Boat Race for the third year in a row, beating Oxford by five lengths.
The Light Blues cemented their dominance over their traditional rivals, new coach Robert Weber's team storming into an early lead and refusing to relent.
Cambridge stroke Lily Lindsay has rowed internationally for the USA, but insisted nothing compared to a Boat Race victory.
"There's nothing like this," Lindsay told the BBC.
"Training alongside my team-mates has been unbelievable. It's been a pleasure."