Even if the Cristiano Ronaldo vs Lionel Messi continues long after both players have retired, as it may well do, the Portugal forward will always be able to point to the day he became the first player to score 100 goals in European competitions.
As both players move into the twilight of their respective careers, they remain the only two men to score more than 100 Champions League goals. And with a 40-goal gap to Robert Lewandowski, who sits third on the all-time list, one would expect them to hold the top two spots with some time to come.
Ronaldo is way out in front, though, as he continues to add to his tally with Manchester United. The 37-year-old scored six European goals for United this season before their elimination, to go along with his 14 for Juventus, but he was still a Real Madrid player when he moved into triple figures on this day in 2017.
Ronaldo didn't score in any of his three European appearances for Sporting CP, or in either of his first two Man Utd seasons. However, he got off the mark when the Manchester club beat Debrecen in qualifying ahead of the 2005-06 Champions League.
Eleven seasons later, the hundred mark was in sight. He took 96 games to score his first 50, having scored just once in his first 32 European games (per official UEFA figures ), but his next 50 came at a rate of more than a goal a game.
He scored more than a goal a game in Europe in four different Real Madrid seasons, including his final campaign at the Bernabeu in 2017-18. However, goal number 100 came in a campaign where that was not the case.
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Part of the reason for this was Ronaldo's slow start. After helping Real Madrid get past his former club Sporting in their first group game, he added just one more goal before the knockouts.
Home and away blanks followed against Napoli - another 180 minutes without a goal in Europe - and Messi was closing fast. Two group stage hat-tricks had taken him to 97 all-time goals in Europe, and Barcelona were playing the first leg of their quarter-final a day before Madrid, so another treble would have seen him beat his rival to the punch.
It wasn't to be, though, with Barca falling to a 3-0 first-leg defeat against Juventus. The very next day, April 12, 2017, Ronaldo made sure things would never get as close again.
The game against Bayern wasn't an easy one, either on paper or in practice. Carlo Ancelotti's side had scored 14 goals in the group stage and put 10 past Arsenal over two legs in the round of 16.
They took an early lead at the Allianz Arena, too, with Arturo Vidal beating Keylor Navas in the 25th minute, and the Chilean missed a penalty that would have put them two up. Might Ronaldo follow Messi in suffering a first-leg defeat? As it turned out, no.
It took him less than two minutes of the second half to get on the scoresheet, getting on the end of Dani Carvajal's cross to send the ball into the corner of Manuel Neuer's net. A red card for Javi Martinez swung things further in Real Madrid's favour, but Neuer continued to keep them at bay until Ronaldo finally found a breakthrough in the 77th minute.
Despite the first-leg deficit, Bayern didn't surrender when they travelled to Madrid for the second leg. A Robert Lewandowski penalty and a Sergio Ramos goal, either side of another from Ronaldo, took the game to extra-time.
By the time the 120 minutes were up at the Bernabeu, though, Ancelotti's men might have been left feeling it wasn't worth the bother. Ronaldo scored his second of the night, then his third, and Marco Asensio made the result more than safe to send Zinedine Zidane's men through to the last four.
"When he has to be, he is," Zidane said after the second leg against Bayern. "He is unique and we are happy for him and for the team. And for the people who have helped us in the Bernabeu."
The gap between Messi and Ronaldo had widened when the semis rolled around, but the Portuguese star wasn't in any mood to slow down. He added another hat-trick in the semis against Atletico Madrid, followed by two in the final as Real Madrid beat Juventus to become the first team ever to retain the Champions League.
Five years on, Ronaldo has the 150 goal mark in his sights, and his scoring rate means he can feel confident about getting there within the next couple of seasons. And it will take a very long time for anyone to run him and Messi close.
