What provoked Juventus management to grossly miscalculate Henry's upside?
Fifteen years after leaving Juventus, French newspaper L'Equipe released a tribute to Henry, pre-empting his footballing swan song for Major League Soccer club New York Red Bulls.
In a 2-2 draw against the New England Revolution (Red Bulls beaten 4-3 on aggregate), Henry controlled the ball and elegantly curled it into the path of Red Bulls centre-forward Tim Cahill, who poked home a goal.
Henry finished his Red Bulls career on a seven-game goalless run but registered five assists in his last five MLS games occupying the left wing.
The same flank which probably draws out a heavy sigh of regret from former Juventus manager Carlo Ancelotti when he reflects upon his fleeting interactions with Henry.
"I didn't think I could play Henry in the middle," Ancelotti said, per Philippe Auclair's book Thierry Henry: Lonely at the Top. "He never told me he could."
"It was one of Juventus' worst seasons," Henry said, per Simon Evans at Reuters. "[Marcello] Lippi wanted to play me as a centre-forward... then Ancelotti arrived and I played the remainder of the season on the left... I had to cover the whole left side."
The year is 1999.
Ancelotti, an inexperienced manager with no history of being a winner, is thrown into a sink-or-swim situation at Juventus, an under-performing heavyweight languishing in mid-table.
He lacks the credentials to replace Lippi, who won three Serie A titles and led Juventus to UEFA Champions League success.
Then there are rumours of Ancelotti's tactical rigidness causing Zinedine Zidane to consider leaving Juventus, per Corriere dello Sport (h/t Jon Brodkin and Michael Walker at the Guardian).
Zidane had already leveraged Juventus by venting that his lifestyle was more important than his job, per The Independent.
For Ancelotti, pacifying the ego of Zidane and stabilising Juventus were more salient objectives than experimenting with Henry's position.
As far as Ancelotti was concerned, Henry was a winger, a view shared by many footballing aficionados in the know, like Harry Redknapp.
"The first time I saw Thierry Henry, he was playing on the left wing for France's U21 team against Norway," Redknapp said, per his book A Man Walks On to a Pitch: Stories from a Life in Football.
"Henry looked as if he had plenty of skill, [though] it wasn't immediately obvious that he was going to become one of the Premier League's great goalscorers."
What further hindered Ancelotti from maximising Henry's world-class ability was Henry himself.
He was complicit in his own identity being slotted away on the flanks.
"I'll play [at Juventus] as I did at Monaco, on the wing, either on the left or the right," Henry said, per Paul Joseph's book Thierry Henry: Fifty Defining Fixtures. "I'm not like David Trezeguet. People shouldn't expect bagfuls of goals from me."
Two years earlier at the 1997 FIFA World Youth Championship, Trezeguet outplayed Henry when the duo were a strike partnership under Gerard Houllier, per FIFA.com:
France's most dangerous spearhead: between them, the team's twin strikers David Trezeguet (No. 11) and the captain Thierry Henry (No. 9) scored eight out of a total of 10 French goals.
Trezeguet (five) and Henry (three) got all but two of the team's 10 goals.
They were able to create good chances for each other; three assists were provided directly by Trezeguet and two by Henry.
In terms of "bagfuls of goals," neither Henry or Trezeguet fitted that description when compared to Brazilian youth international phenom Adailton.
Adailton entered the tournament with eight goals in qualifying and proceeded to accumulate an incredible 10 goals at the Youth Championship, per FIFA.com.
Henry recalibrated his thought process because he believed that, in the long run, he would find more success as a No. 11 than a No. 9.
"When you play as a winger, you have to assist the game, help the left-back, [and] it's not your job to score," Henry said, per Amy Lawrence's book Invincible: Inside Arsenal's Unbeaten 2003-2004 Season.
"I was saying to myself: 'Hang on a minute, I am in the [French] national team, I won the [FIFA] World Cup as a winger. Am I wasting my time trying to relearn being a striker?'"
Under contract at Juventus, Henry was on a plane when he coincidentally bumped into his former Monaco boss Arsene Wenger, the manager of Arsenal.
"Thierry," Wenger said, per Andrew Anthony at The Observer (h/t the Guardian). "You are wasting your time on the wing. You are a No. 9."
The sliding doors moment of meeting Wenger could have planted seeds of doubt in Henry's mind, whose "dream club" was not Juventus—it was always Arsenal, per Chris Taylor at the Guardian:
Arsene Wenger tried to sign Henry in the summer and he described Arsenal as his 'dream club'.
Arsenal were put off when Monaco doubled the asking price after Henry's World Cup exploits.
Since the collapse of his Arsenal move Henry has spent much of the season sulking on the bench as Monaco's fortunes have plummeted.
Yes, there is culpability on Ancelotti's side for not recognising Henry's untapped potential as a No. 9.
But what pushed Henry away from Juventus was not Ancelotti's fault.
Henry pragmatically adapted to life out wide and was beginning to rectify his slow start.
"In the last five or six games [under Ancelotti] I either scored or set up a goal," Henry said, per FourFourTwo. "I left Juventus for other reasons, which I've never wanted to go into."
Those "other reasons" are a reference to ex-Juventus executive Luciano Moggi.
"Then something happened with Moggi which I didn't like," Henry said, per Charlie Caroe at the Telegraph. "If that hadn't happened, I would probably have continued to play for Juventus."
It is natural to speculate that something nefarious was involved, given Moggi's name is synonymous with skullduggery having been implicated in a match-fixing scandal, per CNN.
But the probable explanation to Henry's relationship breakdown with Moggi is less nefarious and more to do with amour propre.
Post-Juventus: Henry scored 228 goals at Arsenal, won a Champions League title at Barcelona and became a franchise player at the Red Bulls.
"Thierry is one of my best signings," Wenger said, per Patrick Goss at Sky Sports. "I'm sure Juventus now regret selling him."
When not specified, statistics via WhoScored.com