If you had told any hurling fan in January this year that Cork would eliminate the All-Ireland champions on the way to a Munster final, they'd have laughed at you. And that includes the fans of the Rebel County.
In 2016, Cork leaked points, and there was doom and gloom for the future. They won none of their league games, conceding twenty points in all of them. In total, they shipped 9-143 in six matches. In the Championship, they were beaten by half time against Tipperary. In the qualifiers, they had a hard fought win over a Dublin team is disarray and went out tamely to Wexford.
Fans and pundits alike were prophesising doom. Kieran Kingston would have a huge job on his hands to turn the Rebels into contenders for Munster, let alone an All-Ireland.
Fast forward to Sunday evening and Kingston has steered his men past Tipperary and has just eliminated a much fancied team who were a puck of a ball away from an All-Ireland final last year.
The entire management team has been instrumental. Thirteen of the Cork panel on Sunday were under 23 - with Kingston bringing in John Meyler, the manager of the under 21's as a selector. Add to that a new strength and conditioning coach, and a Rock.
When you were on a pitch against Diarmuid O'Sullivan, he'd let you know where he was. We can only assume that he's the exact same as a coach.
On Sunday, if a Waterford player picked up the ball in the Cork half, he would be surrounded almost instantly by red shirts. Some might call it a blanket defence, but the sheer swarm of defenders would pay dividends.
All of this is perfectly captured by a Bill Cooper hit with twenty minutes to go.
First off, Jamie Barron is surrounded in a square by Rebels. He offloads to Kevin Moran.
Moran, believing he has space, takes the ball on the run. Cooper has recognised the situation though, and lines up the hit.
BANG. Just as Moran lands, he's nailed by Cooper.
Again, Cork swarm, with five defenders around Moran. Cooper harries the man he hit, who coughs up possession, it falls to Lehane and Cork extend their lead.
And they didn't leave it at that. What summed up Cork's performance was that this intensity last for 70 minutes. Instead of resting on the laurels of an inspirational moment, they were right back to it.
The resulting puck out from Stephen O'Keeffe falls the way of Moran, with Maurice Shanahan again the target.
Although it seems to be a one on one battle, Cork have two more defenders waiting for the break. One of them, Mark Ellis, swoops in and the sliotar goes up the other end for another Cork score.
A combination of the O'Sullivans - Diarmuid as defence coach and Declan as strength and conditioning - brought that passage together.
Four of the starting six Waterford forwards were subbed off, including Austin Gleeson and both Bennett brothers. Maurice Shanahan, so often the target man, contributed just 1-1. Damian Cahalane gave him no space whatsoever.
Not only were they impactful while defending, the Cork backline had an impact when bursting out with the ball.
Mark Coleman had three assists and a magnificent point from a sideline cut. Diagonal balls were consistently pumped from the half back line into Conor Lehane and Luke Meade. Anthony Nash's puckouts would more often than not go to Coleman by the sideline.
It was an attitude that we haven't seen from Cork in years. Even when they got the All-Ireland final in 2013, their defence was questionable, as Clare proved in both finals.
Over the last few years, Cork have tended to fall flat on their face after major performances. Now, they've strung together back to back wins where they outplayed their opponent.
Should they do so once more against Clare in two weeks, an All-Ireland semi-final awaits, with at least two of Kilkenny, Tipperary, Limerick, the Banner and Waterford to exit before then.