It speaks volumes about Cristiano Ronaldo 's sustained brilliance that a five-game drought is a crisis.
But there is no denying the Manchester United talisman has failed to live up to the world-class standards expected of him since the turn of the year.
Ronaldo, 37, has not found the back of the net since the 3-1 victory over Burnley in late December, and the Clarets themselves were the latest team to frustrate him in a 1-1 stalemate on Tuesday night.
The Portuguese striker dropped out of the starting XI for the trip to Turf Moor and was introduced midway through the second half, struggling to make an impression in the search for a winner after Jay Rodriguez cancelled out Paul Pogba's opener.
Ronaldo made straight for the tunnel at the full-time whistle, which not only marked two points dropped for United, but also an unwanted milestone for the five-time Ballon d'Or winner.
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Having also failed to score in January's Premier League clashes against Wolves, Brentford and West Ham, as well as last Friday's FA Cup tie with Middlesbrough, Ronaldo is without a goal in five appearances.
Astonishingly, this is his longest barren run at club level since his early days at Real Madrid, when he went five games without scoring between May and September 2010.
Although he was benched against Burnley, Ronaldo started the other four games during his current troublesome spell and played 120 minutes against Middlesbrough before United were defeated on penalties.
He converted his spot kick in the shootout but crucially missed from 12 yards just 20 minutes into the fourth-round encounter.
Ralf Rangnick hinted Ronaldo's exertions against Middlesbrough contributed to the decision not to start him against Burnley, emphasising the need to "sprint" and press Sean Dyche's side.
"Today it will require a lot of sprinting, chasing balls, a lot of fight for second balls," the United interim manager said ahead of kick-off. "This best fits the profile for Edinson Cavani which is why he starts today."
Rangnick's admission serves as a reminder that even Ronaldo, famed for his phenomenal physical condition, is culpable to losing a yard of pace having celebrated his 37th birthday last weekend.
His age has not stopped him producing many a magical moment since his return to Old Trafford last summer; his late Champions League heroics in against Villarreal and Atalanta were spectacular, as was his tally of six goals in the group stage.
He is yet to make an appearance under Rangnick in European competition, with those memorable nights coming during the reigns of Ole Gunnar Solskjaer and caretaker Michael Carrick.
Indeed, only two of Ronaldo's club-leading 14 goals for the season have come since the German took over as interim manager.
Rangnick has experimented with various formations - shifting from 4-2-2-2 to 4-3-3 to 4-2-3-1 - and tinkered with various attacks while chopping and changing the likes of Bruno Fernandes, Marcus Rashford, Jadon Sancho and Anthony Elanga.
He is yet to unearth the system which will get the best out of Ronaldo, and time is running out to do so with the top-four race growing more fierce by the week.
Benching the former Juventus star does not seem to be the answer, however, as Ronaldo has not scored in his last 10 Premier League substitute appearances, a run which extends back to his goal against Wigan Athletic in December 2006.
So, while his work rate will continue to divide opinion, questions will be asked of his age and he is enduring his driest spell in front of goal in over a decade, Rangnick is expected to recall the veteran forward for Saturday's lunchtime encounter with Southampton.
After all, it would take a brave punter to bet against Ronaldo responding to his critics emphatically yet again, just as he has throughout his record-breaking career.
