Cristiano Ronaldo scoring a free-kick used to be a common occurrence; now they're something of a collector's item.
The Portuguese hasn't scored a free-kick in club football since the 2017 FIFA Club World Cup final and a deflected strike in a pre-season friendly is the closest he's come to doing so for Juventus.
While, yes, THAT goal against Spain at the World Cup was a spectacular anomaly, we're talking about a player that scored 44 goals from free-kick during his first 12 seasons in the sport.
Since then, Ronaldo has only found the net with nine free-kicks from 174 attempts since 2014, giving him the worst success rate (5%) of any player to have scored at least five in that time period.
So, what on earth has happened to Ronaldo's free-kick taking in the last six years? In truth, we might never discover the answer, but some fresh analysis could be the closest we'll ever come.
Sports scientist's analysis
That's because sports scientist and physical therapist Dr. Rajpal Brar has analysed the changes in Ronaldo's famous knuckleball free-kick on his YouTube channel '3CB Performance'.
The 10-minute video goes into everything from Ronaldo's striking technique, his increase in lower body injuries since the decline and even the psychology of his iconic run-up routine.
Coming from an expert such as Dr. Brar, it makes for a thoroughly interesting watch, so check out the full video down below and keep scrolling for our breakdown of the various points included:
Patterns emerge
One thing that Ronaldo certainly hasn't lost in his free-kick taking is the power, but two things have become clear from his post-2014 misses: lack of lift and absence of unpredictable movement.
On tape, there are no discernible changes in Ronaldo's technique with the vault step and foot landing remaining consistent, although it's feasible that micro-details might be at play.
Swing leg velocity, contact point, trunk angle and ball spin-rate are all areas in which discrepancies may have emerged without them necessarily showing up on camera.
It's NOT because of the footballs
As much as different ball characteristics have been proven to impact the flight of a shot, there is insufficient evidence to show that anything of note has changed before and after Ronaldo's decline.
Across his spells with Manchester United, Real Madrid and most recently Juventus, Ronaldo has flitted between Nike balls in the league and cup and Adidas balls in the Champions League.
There have been no greater alterations in the ball technology over the last six years than there was across the first 12 seasons of Ronaldo's career, which didn't affect his proficiency from free-kicks.
Injuries?
Ronaldo has suffered an increase in low body injuries in the time his free-kick taking has waned and it's feasible that these sustained stresses have negatively impacted his striking technique.
Admittedly, though, this would likely be apparent in other areas of his game, which has not been the case.
Rather, Dr. Brar suspects that the injuries will have hampered Ronaldo initially and the 'snowballing' of misses which he wouldn't have been used to started to affect him psychologically.
A change in routine needed?
Speaking of the mental aspect of free-kick taking, Ronaldo has gotten himself into such a negative cycle, that one of the solutions posited would be to change the routine he's used for so long.
Ditching the rhythm that may be causing 'over-thinking anxiety' would perhaps disassociate Ronaldo with his recent struggles and help him simplify the process down to the essentials.
A positive case study of this tactic is NBA player DeAndre Jordan who, after struggling with free throws with his usual routine, regained his form by trying a new approach.
Only Ronaldo truly knows
Other potential solutions posited by Dr Brar include taking a break from free-kick duties or moving away from the knuckleball technique for a more Lionel Messi-like tactic.
It must be said, the research is fascinating and gives more insight than ever on one of the biggest mysteries surrounding a true sporting great in Ronaldo.
Ultimately, though, even an expert like Dr Brar can only speculate on the strange trend in Ronaldo's game and perhaps the man himself doesn't even know why he's lost his touch.