It was in 2019 that Jose Mourinho was asked to describe several of his former Chelsea players in just a single word. For Didier Drogba, it was "legend". John Terry was hailed as a "leader" by the Portuguese. Michael Essien, meanwhile, was called a "son" by Mourinho, who coached the midfielder both at Stamford Bridge and Real Madrid.
Then there was Diego Costa. The Brazilian-born striker spearheaded the attack during Mourinho's third Premier League title win as Chelsea head coach. He snarled. He scuffled. He scored. And that is why when tasked with choosing one word to describe Costa, who spent three seasons at Stamford Bridge, Mourinho simply replied: "Animal." It remains an apt description.
Chelsea had never owned a striker quite like Costa. They're unlikely to in the future either. The Spain international was unpredictable and combative; a player equally capable of scoring a hat-trick or connecting with a headbutt. Perhaps even in the same game. It's why he was so adored by Blues supporters. He may have been a pantomime villain, but he was their pantomime villain.
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Nobody in Thomas Tuchel's squad quite matches up to Costa. Antonio Rudiger is probably the closest in terms of chicanery and aggressivity, but the German centre-back is down a rung or two on the ladder when compared to the weekly antics of the Blues' former No.19.
Chelsea's current first-choice forward, Kai Havertz, certainly doesn't have the same fiendish quality. He is far more controlled and less easily riled. "He is simply not that guy that you will fully feel or see enraged," Tuchel stated last year. "For some, you feel they have to fight with others to get a certain momentum. He is not a Diego Costa kind of guy, this is simple, and I will never demand he will become this."
Yet Havertz isn't completely clean-cut, and there have been flashes of aggression shown by the 22-year-old this season. For instance, he went nose-to-nose with Trent Alexander-Arnold during the Carabao Cup final after being provoked by the Liverpool full-back. Although admittedly, it was a spiky incident that wouldn't crack Costa's top twenty altercations.
What Costa and Havertz do share is a dogged determination to hassle and harass opposition defenders when not in possession of the ball. The former did it in more of a wrecking-ball fashion when compared to Havertz, whose pressing game was refined from an early age in the Bundesliga.
That readiness to try to win back possession high up the pitch is a key reason why Havertz has usurped Romelu Lukaku and Timo Werner in the pecking order to be Chelsea's number nine under Tuchel. And it was on display at the weekend despite the Blues suffering a shock 4-1 defeat to Brentford at Stamford Bridge.
Per FBRef, no player attempted more pressures than Havertz (16), and as a result, no player made more blocks (4). He also led in successful dribbles (2) and aerial duels won (4) while was second to Rudiger – of all people – for attempted shots (4). The disappointment is, of course, that none of those found the back of the net.
However, during a second half in which Chelsea conceded four goals and many players produced frustrating performances, Havertz continued to work hard, continued to push to try to swing the game in his side's favour. That his efforts didn't prove fruitful should not be held against him.
They certainly weren't by Tuchel after the game. "I felt he was our strongest player," the Chelsea head coach stated. "I think he worked like an animal and was very dangerous. I am very happy with his performance in particular."
Havertz is a very different kind of animal to Costa, but the 22-year-old has proved he can be as effective for Chelsea on the biggest of stages. The challenge for the German remains to produce week in, week out. To show the same fight that was displayed against Brentford time and time again.
