The attacker, who grew up in the same area of Paris as Kylian Mbappe, had long attracted admiring glances from some of Europe's biggest clubs, so PSG were eager to not let another get away.
Two years earlier, Kingsley Coman left for Juve when it became clear a route into the starting XI – and the France squad – was more straightforward in Turin than in Paris and, although injuries have since disrupted his career, there's little doubt PSG have been made to rue their ineptitude on that front.
Ikone's emergence was supposed to redeem PSG. For much of the QSI era, their use of homegrown young players has been heavily scrutinised.
"Jonathan is a midfielder with a big future," club president Nasser Al-Khelaifi said after the contract was announced. "His signature is another example of the importance the youth academy holds for the club and just how much the club is counting on these young academy graduates."
But in 2018, PSG sold Ikone to Lille for a relatively insignificant fee – and the player has blossomed since his departure.
False hope and new beginnings
After helping PSG to the UEFA Youth League final in 2015-16, Ikone's new contract was followed by promotion to the first team. He made a smattering of appearances before being allowed to join Montpellier on loan in January 2017.
This spell provided Ikone with his first genuine exposure to first-team football, playing 14 times in the second half of the 2016-17 Ligue 1 season.
He returned to Montpellier for the following campaign and, while it was not quite as fruitful as his first stint at the club, he did enough to earn a reported €5million switch to Lille, whose applaudable transfer policy in recent years has seen them snap up a host of well-regarded young players.
"We can say that PSG train young players very well, but actually playing there is complicated," Ikone told L'Equipe last year. "But the training you get in Paris, it's the best. Really, I enjoyed my time at PSG. I have no regrets. Getting playing time there is difficult, there are really great players there. So, I decided to show my talent at another club."
The transfer again raised doubts from some with respect to PSG's handling of their academy, while others suggested Ikone had not done enough to earn fresh terms, with the chance to earn a reasonable fee too good to turn down for PSG given his deal was due to expire in 2019.
Lille are reaping the rewards and will likely earn a significant fee when – if – he eventually leaves, with the latest reports suggesting he could be bound for the Premier League and Everton. At least PSG managed to secure a sell-on fee, which could amount to as much as 40 per cent of €70m, Les Dogues' apparent asking price.
Establishing himself
Although his skill set makes him a versatile option in attack, Ikone is at his most threatening when deployed as a no.10, behind the main striker.
The inside-right channel is where he operates most often, coming inside on to his left foot, allowing him a greater range of options whether he's dribbling, looking for a disguised pass or simply feeding Victor Osimhen into the space beyond defences.
Having been a regular option throughout the French youth setup, Ikone earned his first call-up to the senior side in September and netted on his debut, becoming the first player to do so for Les Bleus since Younes Kaboul and Marvin Martin in June 2011.
Skilful and inventive on the ball, there is a lot to like about Ikone, but he will not need anyone to tell him that staying in contention is not going to be an easy job.
France are blessed with a host of options in attack, many of whom boast similar strengths to Ikone.
Menacing but not in it for the long haul
Having scored three and set up nine goals in Ligue 1 last term, Ikone cannot be accused of a lack of consistency or taking a drastic backwards step. With a chunk of the season still remaining, he has the same amount of goals and six assists.
Ikone is averaging a goal involvement every 230 minutes, five less than last term, and appears to be playing with even greater confidence.
After averaging 3.6 dribbles per game in 2018-19, that's increased to just under five in 2019-20, while his completion rate has remained almost identical at 55 per cent. By comparison, Neymar's is 56 per cent.
Nevertheless, Ikone's productivity in the final third has significant room for improvement.
With 31 key passes, he is way behind the likes of Dimitri Payet (87), Angel Di Maria (77) and Zinedine Ferhat (52).
There are also doubts about his endurance. Since the start of last season, Ikone has been taken off 43 times in Ligue 1 alone.
But, at 21, he is developing impressively. While €70m may look a little steep at the moment, any potential buyer will hope there is still plenty more to come.
