When an exciting new talent arrives on the European scene, we instantly search for legends past or present which to compare his style or stature.
Paulo Dybala was swiftly dubbed the new Lionel Messi due to his Argentinian heritage and slight, diminutive build. Christian Pulisic drew immediate comparisons with the man he replaced at Chelsea, Eden Hazard.
In the case of Kai Havertz, he would probably admit himself that his football doppelgänger is national compatriot Thomas Muller. Standing an inch taller than Muller at six foot two, the new Chelsea star sticks out like a sore thumb from the majority of playmakers in the modern game.
It's not only height and an unfashionable figure which Havertz shares in common with Muller, though. He is following in the Bayern man's footsteps by becoming a genuine, top-class attacking midfielder, and like Muller, his game is all about space and anticipation.
In fairness to Havertz, he also has pace on his side, and is often a clear winner in a footrace with most centre-backs. That is not where he makes his mark, however. For the 21-year-old, it's all about reading the game, understanding the gaps between defenders and exploiting them ruthlessly - much like the more experienced Muller.
Now, for a boy who has barely left his teenage years behind to be working on mental wavelengths of that nature is insanely good going. And for the worried Blues who have yet to see their big-money summer signing sparkle as of yet, there is cause for optimism.
"He is a very good player, if not the best player of his age group in Europe at the moment. His skills are exceptional. Of course, we always want the best players at Bayern"- Thomas Muller on Havertz
There is no doubting his ability, nor whether he will be able to cut it in the Premier League. It's only a matter of time before he successfully applies the same mental arithmetic that he learnt to calculate in Germany on the English stage, too.
It's no fluke that he's grown to become as highly rated as he has, nor is he a one-season wonder.
Havertz exploded onto the Bundesliga scene as a mere teenager, becoming the youngest player to pull on the Bayer jersey at the time, and then breaking another record to become the club's youngest ever goalscorer. His talent and knack for the game was obvious from the off, but there was something particularly special about his style of play.
He wasn't your typical, inexperienced, blood and thunder newcomer. He was measured, calm and collected, always assessing his options and never quick to rush anything. He was a wise, old head on young shoulders.
Over the next four years, Havertz quickly made a name for himself as the brightest spark in the future of German football, and wowed viewers with his ghost-like movement and ability to time any pass or run with unerring ease.
His graceful glide across the pitch caught the eye, patrolling the final third like a shark, waiting for some poor soul to take his bait.
He drew instant comparisons with Muller, as he operates in similar areas in the final third which most ordinary players daren't enter. He feeds off defenders' slightest movements, reacting to a misplaced step out of line quicker than any other player can anticipate, and shows ice-cold composure when in front of goal.
Havertz has also perfected the arcing run inside the full-back to escape his marker and bear down on goal, and he demonstrated on countless occasions for Bayer that he can finish from even the most acute of angles, no matter how much of the goal is covered by the shot-stopper.
"He has developed enormously at Leverkusen. He moves very well between the lines, is quite fast, safe on the ball and is good at finding space. He has got a strong goal-scoring instinct at a young age"- Hansi Flick on Havertz
It's not only running in behind where he earns his money. Like most attacking midfielders, Havertz thrives on late runs into the box, arriving untracked and using his tight control or superb first-time finishing to tuck the ball home.
It's this natural instinct and awareness of his surroundings which makes him so good, something that can only be nurtured from a deep love of the game, and a desire to become the very best in one's field. With such an array of technical skills, it's no wonder he's rated as world class.
Statistically, his goals and assists return during his time in Germany was off the charts for a kid of his age. He managed seven goals and 13 assists over his first two seasons as a professional, and while they weren't frightening numbers, they were a warning sign of what was to come.
By the start of the 2018/19 campaign, Havertz had sized up his opponents, contemplated his own abilities and decided, "Yeah, I'll have a bit of that." While he only managed three assists, he scored more than double the tally he'd achieved in his first two years, bagging 16 in the Bundesliga, and becoming the main man to round off the moves as much as supplying them.
He then upped his assists for his teammates, notching six in 2019/20, while adding a more than respectable 12 league goals to his total. He reached that dozen with an expected goals rate of 9.53, showing just how clinical and efficient he could be in the box.
Much like Muller then, Havertz has been gifted with the goalscoring instinct, while also appreciating the art of a good assist. Merciless, creative and selfless in good measures.
This excellent form also stretched onto the European scene, where he scored four goals in five matches, putting himself in the shop window for the big boys. He slotted home a penalty against Rangers in the Round of 16, taking on the responsibility with nonchalant ease.
As far as big stages go, he's yet to enjoy the heights that his talents merit. He did grace the 2020 DFB-Pokal Cup final with his presence, as Leverkusen took on eventual treble-winners Bayern, and he gave a brilliant account of himself.
"We’ve had many good players through the history of the club at Bayer Leverkusen, but Kai Havertz is the best of them all."- Rudi Voller on Havertz
A 4-2 defeat far from told the whole story, as Havertz rattled Die Roten from the first whistle, carving out three or four gilt-edged opportunities, only for his wasteful teammates to squander his handy work. Their poor finishing was punished, and Bayer's starlet could only console himself with a last-minute penalty - which he expertly dispatched.
It was apparent from that display that he did not deserve to be on the losing side, and he was ready to be tested at the highest level. Now at Chelsea, Havertz has been presented with the opportunity to show the world what we already know: he is destined for greatness.