Playing Kai Havertz as Chelsea’s main striker would not have been part of Thomas Tuchel’s grand plan back in August.

Romelu Lukaku’s arrival was meant to be the final piece of the puzzle for the Blues as they looked to challenge Manchester City and Liverpool for the Premier League title.

But the Belgian has struggled while Havertz has hit form, prompting Tuchel to start the German up front in recent games.

Will that continue tonight at Norwich, or is Lukaku in line for a recall?

Havertz shines

Though Havertz, 22, has started six of Chelsea’s last seven games, only the past three have come as the centre forward — and he has shone.

After Lukaku managed just seven touches against Crystal Palace, Tuchel opted to go with Havertz as his striker against Lille and the switch has proven a masterstroke.

He scored early on against the French champions, was outstanding in the Carabao Cup final defeat to Liverpool and bagged two goals in the 4-0 thrashing of Burnley.

Havertz is no false nine either. He drops off the centre-backs to pick up the ball, has the intelligence to know when to run in behind and is also an underrated poacher.

He netted a brilliant header against Lille and two close-range finishes against Burnley, coming after his confident penalty against Palmeiras in the Club World Cup final.

Former Chelsea star Joe Cole even likened his display against the French side to the sort Roberto Firmino produces for Liverpool.

Cole said: "Havertz reminds me of a [Roberto] Firmino for Liverpool, someone that knits it all together, he was a nightmare to mark.

"He comes alive in the box, wherever he plays. This is what I like, passion, penetration, taking your team forward – that is brilliant."

Teacher’s pet

Tuchel was effusive in his praise for Havertz after the victory at Turf Moor last Saturday.

He said: "He gives a lot of intensity and he’s involved in goals. He scored again, so it’s a very good moment and it’s on him to keep going. This is how it is.

"We played the last cup match without him, Timo Werner was very strong and was very close to starting. Romelu got his goal and we will need everybody. But at this moment, [Havertz is] in really good shape.

"What he gives us is huge volume. He covers a lot of metres, he covers a lot of metres in high intensity, so he finds the intensity no matter what the system the opponent defends against us, he finds intensive runs, he finds distances.

"This is what makes him and he uses his body more and more.

"He loves to create overloads and half spaces and this is what he gives. It’s just his style of play, his characteristic as a player. He’s in good shape, he’s confident."

Bad news for Rom

Given Lukaku has been accused of being lazy in the past, that is not good news for the 28-year-old.

The ex-Inter Milan forward is never likely to put in the hard work defensively that Havertz does.

Despite his profile, he has also never been an archetypal target man. Holding the ball up and bringing others into play is not his favoured role.

Lukaku likes to run at defenders and to get in behind the backline — he will certainly not just sit between the 18-yard lines looking for the ball to feet, or sniffing out goals.

The stats

Given Werner has not started a league game since November, the conversation as to who makes the XI is currently between Lukaku and Havertz.

The Belgian has five goals in the league, while Havertz is one behind on four — neither have set the world alight, in that regard.

Lukaku has created 16 chances compared to Havertz’s five, though the German has an assist while the summer signing has none.

It is in the rest of the work where the ex-Bayer Leverkusen man is clearly ahead of Lukaku though.

He has attempted 377 passes, including 187 in the final third, compared to Lukaku’s 224 with 117 in the final third, as well as enjoying substantially more touches.

Defensively, Havertz wins the ball back more all over the pitch and contests more duels too.

In the modern game, these are all things strikers need to do.

Space for both

Clearly, Havertz is the man of the moment for Tuchel. But that does not mean it will always be this way.

The 23-cap international has blown hot and cold throughout his time at Stamford Bridge and is yet to prove he can keep up his stellar performances over a sustained period.

With the Blues still battling on three fronts — for a top-four spot in the Premier League, as well as FA Cup and Champions League glory — Tuchel will make changes to his system and personnel against different opposition.

Havertz may well start again tonight after his Burnley display but there is every chance Lukaku will get a chance against Newcastle on Sunday, or at Lille next Wednesday.

If he does, the Belgian needs to grab it with both hands if he is to stop Havertz making that No9 spot his own.