WHEN Virgil van Dijk named Nicolas Jackson as his most feared opponent last season, there would have been more than a few chuckles.
The Chelsea striker has faced plenty of ridicule since arriving in the Premier League in a £30million deal.
But people may now realise what Liverpool skipper Van Dijk was on about.
Jackson, 23, was rested at Southampton in midweek but will surely return at Tottenham on Sunday, a ground where he bagged a hat-trick in a 4-1 victory last season.
The three goals there last season were handed on a plate by a nine-man Spurs playing a daft high line.
That treble was labelled in some quarters as one of the most disappointing in Premier League history, just one example of how Jackson became the butt of many a joke.
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Despite that criticism and pressure, Jackson managed 14 Premier League goals in his first campaign in English football.
And he has more than kicked on from there, proving that Chelsea had no need to chase Napoli striker Victor Osmihen in the summer.
The club pushed hard to add more firepower, but their loss has been Jackson’s gain and, with hindsight, likely a benefit to the whole Stamford Bridge squad.
Those who know the former Villarreal man credit a supreme self-belief for helping him battle through the doubters to become a key figure in this resurgent Blues side. It is not only in west London there have been hurdles for Jackson.
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He grew up playing street football in Senegal and did not own a pair of boots until the age of 16.
At Spanish LaLiga side Villarreal — after a move to Bournemouth collapsed — he returned not with his head down but a flurry of goals which secured a big-money transfer to Chelsea.
Fighting through some difficult times, has brought Jackson to his purple patch at Stamford Bridge.
There has always been an inner steel which, for some time now, has been supported by a close network around the player, as well as the staff at Chelsea.
Jackson has long had a dedicated team managing nutrition and fitness and is now reaping the rewards.
This is no story of a switch flicking in the summer but years of work bearing fruit.
The one change staff at the club have noted since the turn of the year is maturity.
By this time last season, Jackson had already served a one-match ban for picking up five yellow cards.
Only one of those was for a foul, the rest for pure petulance.
He does, admittedly, already have four to his name this season, but progress is progress no matter how small.
Boss Enzo Maresca still wants to see that side of his game improve, but there have also been steps forward when it comes to efficiency in the final third.
Jackson is showing more know-how and selflessness when it comes to either teeing up a team-mate or having a go himself.
And staff have also been pleased with his work off the ball as the Blues battle to become more consistent defensively.
Most of all, his willingness to work and adapt to new ideas has been most pleasing.
Maresca said recently: “Since we started, he has been open-minded in what we ask him, and sometimes we require different things from him.
“He has an open mind and wants to learn and he’s doing very well, not just in goals and assists, but also the way he works off the ball.
“The way he presses, he is always aggressive and we are very happy.
“For sure, this season he’s had one-v-one chances he has missed — that can happen — but he can improve that area.
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“He can be a bit more brave on the ball when we need to link with him.
"But overall, there are many areas he’s already improved a lot.”