It's been a question that Jose Mourinho has considered answering without ever fully revealing his thought but at around 6:15pm today, when the teams are confirmed, we'll at least know his Plan A in combating the absence of Harry Kane.
Mourinho has been consistently asked about the prospect of resting Kane this season, such is the captain's workload, but after the striker sustained two ankle injuries against Liverpool on Thursday has been forced into accepting he will simply have to.
Kane's presence is eternally reassuring because not only does he promise goals, creativity and just an overall presence on the field but he also, to an extent, dictates what formation and system Spurs should play.
He is a tactically flexible player but a team can still be formed around Kane, where Spurs can extract the best from him and he can elevate the level of his teammates.
The major decision for Mourinho, as much as who replaces Kane, is how he selects a system without his talisman.
The tried and trusted 4-2-3-1 has been briefly abandoned, with Mourinho reverting to a 3-4-3 against Liverpool and Sheffield United, with mixed results.
The closest like-for-like, which would eradicate a lot of this debate and conjecture, would simply be to pick Carlos Vinicus; an orthodox centre-forward, the Brazilian can be stationed in either formation with runners and wingers around him.
It would maintain Son Heung-min's position attacking from the left, and also then give either Steven Bergwijn, Lucas Moura or Gareth Bale a role doing the same from the right flank.
Of that quartet, only Son is likely to play centrally in place of Vinicius, should Mourinho deem his lack of Premier League experience doesn't yet make him a credible pick.
The Spurs manager has already stated neither he nor Bale see the Welshman as a striker and Bergwijn or Lucas wouldn't be much use against Brighton's physically imposing backline ... then again, maybe that could be exactly the point.
But the smart money is on Vinicius earning a first Premier League start and providing the focal point for the team.
Into midfield, as we work backwards, Tanguy Ndombele simply has to start, no questions asked, as does Pierre-Emile Hjojberg. Therefore if Mourinho does opt for a 3-4-3, they would be his chosen pair.
Should be move back to a 4-2-3-1 that opens up a chance for Moussa Sissoko or Harry Winks, with Giovani Lo Celso injured.
The presence of Yves Bissouma may make Mourinho consider that he needs an extra bit of security and physicality in that area to enable Ndombele to attack.
With wing-backs in a 3-4-3, no Sergio Reguilon, who's out for up to three weeks with a muscle injury, means Ben Davies is the only option. That could, in a way, be the determining factor as to what system Mourinho plays.
Against Liverpool, Davies joined Eric Dier and Joe Rodon as centre-backs. Should Davies therefore be required on the left, does Mourinho has faith in Davinson Sanchez or Toby Alderweireld to fill the third spot?
In the case of Sanchez, evidence this season tells us no. Alderweireld has, slightly surprisingly, been on the bench in four of Spurs' last five games, indicating that Mourinho has doubts over the Belgian veteran.
There is considerable and justifiable cause for reinstating him against Brighton but maybe Mourinho's mind is already made up.
Returning to the formation question, the fact that the Seagulls only tend to play with one striker in Neal Maupay only reinforces the theory that Mourinho will return to a 4-2-3-1.
Which leaves one final, and contentious, position at right full-back, where Mourinho either selects a player out-of-form in Matt Doherty or one he has seemingly lost patience with in Serge Aurier.
Of course, there is also Japhet Tanganga, who could be the wildcard pick, but the suggestion is that Doherty will be given the chance to build his confidence levels and continue some sense of stability at the back.
But with so many questions over this team, it really is a difficult one to forecast.
Tottenham (4-2-3-1): Lloris; Doherty, Dier, Rodon, Davies; Hojbjerg, Sissoko; Bergwijn, Ndombele, Son; Vinicius
