On 12 January, 2008, the Portugal superstar smashed home a hat-trick for Manchester United against Newcastle on their way to a third successive Premier League title - and his own maiden Ballon d'Or.
The Red Devils, led by their legendary manager Sir Alex Ferguson, were the undisputed kings of England and the biggest club in the world.
His hat-trick was a thing of beauty and one that propelled him to world stardom before he departed for Real Madrid in a world-record £80m transfer a year later.
The forward broke the deadlock with a sumptuous low free-kick under the jumping Newcastle wall and into the net to the joy of a jubilant Stretford End.
He got his second of the evening after Carlos Tevez's second, finishing off a sweeping United attacking move to make it 3-0.
His match ball moment was his least special goal, but perhaps one that foreshadowed his switch from tricky winger to an out-and-out goal-scorer.
He kept his composure to control the ball in front of a crowded box and fake the shot before finding the net with his eventual low effort, a 22nd of the season in all competitions.
It was a glorious moment for the then-22-year-old who has gone onto to collect match balls in scores ever since.
But fourteen years and four more Ballon d'Ors later, Ronaldo finds himself on the top of a sinking ship.
Sir Alex has retired, the club have won just three major trophies since he left and Ronaldo has returned to a club in disarray.
He spent nine years away, six with Real and three with Juventus, and the incredible success of his days at Old Trafford are a mere memory.
There's a case to say things are as bad as they have ever been at the moment.
Since Ferguson retired, three managers with brilliant reputation's have come and gone, while a club legend has also faced the axe.
David Moyes departed in just six months, Louis van Gaal was given his marching orders in two seasons, before Jose Mourinho and Ole Gunnar Solskjaer were both relieved of their duties.
The Old Trafford hot seat is seemingly a recipe for disaster and Ralf Rangnick is already finding that out the hard way.
His players don't seem to be buying into his philosophy, while Ronaldo, Bruno Fernandes and Marcus Rashford - as talented as they are - have come under fire during his brief tenure.
Some pundits even think Ronaldo is the problem.
Former Arsenal midfielder Perry Groves said United should ditch the Portugal superstar if he was a new manager joining in the summer.
Asked what the first thing he'd do if he was given the job, Groves responded: "I would make sure that Cristiano Ronaldo wasn't there.
"I'd get him out because he's going to be bigger than every manager that comes in.
"Say [Mauricio] Pochettino comes in, he's going to be bigger than him and you can't have a player who's bigger than the manager.
"Ronaldo will still score you goals but if you want to progress and have the modern, pressing game, high energy, that's not Ronaldo."
Ronaldo is 37 in one month and a return of 14 goals in 23 appearances surely shows it's naive to suggest he is the root of United's problems.
Perhaps the executive vice chairman's Ed Woodward's departure in February can signal the start of a new era of success.
Man United XI vs Newcastle: 14 January, 2008
Van der Sar
O'Shea
Ferdinand
Vidic
Evra (Simpson 67)
Ronaldo
Carrick
Anderson (Fletcher 72)
Giggs (Nani 72)
Rooney
Tevez