The narrative around Dele has always been louder and more dramatic than the truth.
A few things stuck out for me in the article - that his early goals output significantly overperformed xG - this gave a false impression of what output we should expect from Dele: around 7-10 goals a year, not 12-15.
So when you add some context to his performances, he actually has done quite well under Mourinho in his preferred role.
And here's the obvious bit (emphasis mine):
Finally, looking at Dele’s output over his different positions over time, we see that he’s certainly strongest and most comfortable creating when playing in the hole. By just considering positions where he’s played 500 minutes or more in a given season, Dele’s expected goals per position looks like the following:
An xG of 0.46 per 90 minutes this season when playing behind the striker is his best ever at that position, and his second best overall — just behind when he was playing nominally on the left in 2016-17 (often alongside a wing-back in a three at the back system that allowed Dele to play more like a No 10).
Also, 2019-20 is seeing Dele do some of his best creative work, making quality chances for team-mates too. While he only has four assists so far, these figures suggest he’s playing as well as he was when he got nine and 10 assists in 2015-16 and 2017-18 respectively.
For Dele, it’s clear that he does his best work when behind the striker and much of his “decline” has been linked to being forced to play out of position over the last couple of seasons.
The positional side is especially important since Son’s dramatic improvement is a big reason why Dele found himself playing further back for much of last season. He was stationed in a deeper midfielder role for 17 per cent of his Premier League appearances compared to six per cent in 2017-18, which was clearly a contributing factor to his reduced goal threat.
And a bit on conflating off-field and on-field narratives:
One view is that Dele’s fashion interests have been conflated with an idea that he is some sort of party boy. Another is that because Dele is spiky on the pitch and will stand up for himself off it, he is an easier target than those who prefer to simply toe the party line. Dele is not hard-wired like that, though — witness the way he hurled his boots to the ground in frustration after being subbed off against RB Leipzig in February.
That incident again ties in to the theory that Dele is held to different standards. Some thought the reaction petulant, but it came after he had toiled in an unfamiliar false-nine role, covering more ground than any other Spurs player by the time he was taken off. “Every time Tottenham have a bad spell or a bad game, Dele Alli always gets the most stick,” the former Newcastle United and England midfielder Kieron Dyer said on BBC radio a couple of days later.
“For example, if Harry Kane has a bad game, it’s because the team isn’t creating the chances for him. People must realise Dele is a player who gets on the end of things. He’s like a striker. When strikers don’t play well it’s because they haven’t been given chances and it’s the same with Dele.”
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Clearly, his reputation is not quite where it was a couple of years ago, when a massively lucrative move to a club such as Real Madrid looked possible — at around the same time that Pochettino described Dele in March 2018 as the “best 21-year-old footballer in the world.”
But Dele remains in a fantastic position, especially for someone who has only just turned 24 — and the journey he has been on from where he started is nothing short of astonishing. The numbers meanwhile suggest he is having a very effective season and is close to his best.
Perhaps the relative difficulty of the last couple of years will help refocus a player who up until then had known pretty much uninterrupted success. “Maybe it’s been a slightly tough period,” says Robinson. “But knowing Dele he’ll only become a better person and a better footballer because of it.”