Daniel Farke's insistence that he has many options he would trust at number 10 behind Brenden Aaronson may be put to the test this weekend.

Aaronson has started the last 29 straight Championship games, often seeing out the match until the end. The American plays in a busy area of the pitch and possesses a playing style that sees him cover acres of ground.

“I have to stop him sometimes, he's like a bee,” Farke said of Aaronson last week. “He’s so full of energy that you have to make sure energy does not come out of both of his ears and not be too hectic at times. Sometimes I have to make him relax a bit more.”

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Leeds United were open to bringing in a number 10 option during the winter transfer window, but only if he met the strict criteria of being affordable, the required quality and a great character. Farke has indicated that several options were looked at but none ticked “all the boxes”.

He therefore concluded: “For that yes, we go with what we've got.” The risk is clear, given the manager himself admitted he has no direct back-up to the ever-working Aaronson.

Farke added: “Of course we need a little bit of luck that [Aaronson] stays fit and in shape, with no injuries. If something happens we have players - perhaps not specialists - but who can shine in this role and even adapt in the way we play if we have to.”

The boss has previously outlined how he believes Manor Solomon, Wilfried Gnonto and even Joel Piroe can play at number 10, albeit said each would “interpret” the role slightly differently to one another.

Aaronson, though, is the only natural option there and while the playmaker told me he believes he has a good fitness level, it is wise that the 24-year-old takes a break at some point - at the very least from the start, anyway. Saturday’s FA Cup tie against Millwall would be such an opportunity for one.

The USMNT star sat out the 1-0 win over Harrogate Town in the last round as Manor Solomon was tasked with being the number 10. He grabbed the assist for Largie Ramazani’s goal, although that admittedly came from his usual left wing position.

Farke had been asked whether he sees Solomon as his go-to replacement for Aaronson in the role but failed to concretely confirm so, stating that the Israeli’s showing against Harrogate should not be read into that much given the strength of the opposition.

Millwall provide a sterner test and so the question is raised of who will start centrally. Of course, it still might be Aaronson. The lack of direct back-up is an argument for and against fielding him.

Farke was clear in saying he is “never concerned” about Aaronson's energy levels, and that the actual worry is “more like channeling his energy”. But the manager did make a telling confession.

“What you can’t predict is there is always the possibility of booking suspensions… but also the possibility of injury. You can never guarantee [this won’t happen].”

That, right there, is the danger. United would be weaker as a result of Aaronson’s absence and the longer anyone plays without a rest, the risk of injury increases, which is why Farke might be in two minds about playing him on Saturday.

However, fortunately, after Tuesday’s game away at Watford, Leeds have some welcome rest periods between games. United do not play again until the following Monday before having a full week’s break - although the magnitude of those fixtures need not be spelled out.

Sunderland visit Elland Road on February 17 before Leeds travel to Sheffield United on February 24. The Whites will need Aaronson on top form and fitness for those matches.

Farke may deem the interim period between the fixtures as enough rest time for him, which could tempt him to start Aaronson against Millwall. But it is a scenario that could have been avoided.

Acquiring a new number 10 option in January would have negated the need for this conversation. Play it safe, don’t risk Aaronson, wrap him in cotton wool and let the newcomer show what he has got. Instead, all current avenues available to Farke carry an element of risk.

Even if Aaronson is rested, who plays centrally? Can Solomon hack it against bolshier opposition? Would Gnonto be able to cope there, having not started a match at no.10 under Farke? Will Piroe as a false nine keep the balance?

These are all unanswered questions that we could see the response to this weekend, on the back of a transfer window that has left some supporters pensive.