Can Timo Werner upstage Jadon Sancho? Will Erling Haaland outshine Patrik Schick? Or can Dayot Upamecano or Mats Hummels tame the fearsome attacking forces on show when RB Leipzig host Borussia Dortmund on Saturday?
With just three points between them and the duo - in third and second place respectively - level on goal difference, they have been evenly matched all season long.
bundesliga.com focusses on the key battles that could decide what promises to be one of the stand-out 90 minutes of the season.
The fact that, between them, they have scooped up three of the seven Player of the Month awards, and are among the Bundesliga's Player of the Season nominees speaks volumes to this duo's influence on their teams' 2019/20 campaigns.
They certainly claimed centre stage when the sides played out a breathless 3-3 draw on Matchday 13. Werner scored twice in that game - a brace that marked the end of a purple patch of 12 goals in seven consecutive league games - while Sancho netted one and teed up another.
In seven league outings since the restart, Werner has struck five times to move onto a career-best 26 league goals, but the slightly deeper role that Julian Nagelsmann has employed him in this season has also brought him eight assists.
Watch: Werner's big performance in the reverse fixture!
That means Werner has been involved in one more of his team's 2019/20 league strikes than Sancho, one of the rare members of the 'double-double' club for goals and assists in Europe this season.
But the England international has been below-par since returning to action with the notable exception of the hat-trick in the Matchday 29 demolition of Paderborn.
Dortmund will hope Sancho can hit top form while Werner's impending switch to Chelsea and the English Premier League distracts the Leipzig frontman, who - as Nagelsmann is fully aware - is a unique talent that can't be replaced.
"It's not possible, you can't clone a player," said Nagelsmann, who probably would be open to bending science to suit his team's needs if that were possible…
Watch: Sancho's best Bundesliga moments!
And what if the answer to Leipzig's potential post-Werner troubles were Patrik Schick, the man who got the equaliser against BVB in that 3-3 draw?
The Czech Republic forward's start to Bundesliga life was troubled by an ankle injury, but check the division's leading goalscorers' chart and you'll find he's into double figures.
Add in his two assists, and he's been involved in 12 goals in just 14 league starts for Leipzig; he had scored only five times in 46 Serie A appearances for Roma over the previous two seasons before leaving for Germany on loan last summer.
"Just look at the numbers," he told Czech newspaper iDNES when asked if he felt better suited to the style of Leipzig compared to Roma. "We play one-touch football, we're fast and people get entertained when they watch us. We always want to play a spectacular brand of football."
With Yussuf Poulsen sidelined for the game, Schick's presence leading the line will be doubly important. It's a role Haaland will also play, and one in which he'll be hoping to rekindle the form of his first days in a Dortmund shirt.
After a remarkable, record-breaking start to his Bundesliga career, the 19-year-old Norway international has not quite gone off the boil, but his form has certainly cooled.
He has found the net just once in his last four league games - the late winner against Fortuna Düsseldorf that secured UEFA Champions League football for next season - and struck only twice in his last seven Bundesliga outings.
A knee injury certainly slowed his momentum, and Lucien Favre has been careful to try and limit the teenager's contribution in the hope of not burning him out, but to secure second place, the Swiss tactician needs him to be on fire against Leipzig.
Watch: Haaland under the tactical microscope!
"He is 19. It's normal that he is sometimes tired," Favre said before Wednesday's surprise defeat to Mainz, a game in which Haaland played the full 90 minutes, also another surprise.
"We have a plan with him. It is impossible for many players to play three games in one week. We need him. I like his mentality, he always wants to play, he always wants to win. Of course he still has to develop and has so much potential."
There is so little to put between this centre-back pair other than age. There is a decade between the Leipzig man, 21, and his Dortmund counterpart, 31, but on the pitch, you can hardly tell.
Both are pillars of their team's strategies of stopping opponents and starting attacks. Hummels features sixth in the number of touches league-wide this season and has a 90 per cent pass completion. Upamecano, who has played three games fewer with 26 appearances, can boast of hitting his intended target 91 per cent of the time.
The respective rearguards have performed almost identically - Dortmund have conceded three more goals than Leipzig - but Hummels has arguably contributed more to his team's solidity winning far more duels both on the ground and in the air than Upamecano.
The France U21 international comes into the game with just 45 minutes of football in his legs since the rush of blood to the head that saw him dismissed against Paderborn - not the best preparation to face Haaland, Sancho & Co.
"Upamecano isn't playing at his best level right now," admitted Nagelsmann. "He knows he can be better, that's not a bad thing. He's still young. He's got talent, but lacks consistency. You can understand that. He's done some very good things this season, so everything should work out for him in the future." Leipzig need that future to be Saturday afternoon.
Would Leipzig have been even closer to Dortmund in the table if Kampl had been able to play more this season? Quite probably.
The Slovenia international has managed just nine league appearances in 2019/20 due to a lengthy and unfortunate list of injuries, but has won five of those games and has yet to taste a league defeat this term.
He's much more than a lucky mascot too, contributing two goals and as many assists in just seven starts, and after six months on the sidelines, came back for the 1-1 draw with Freiburg on Matchday 26 and covered more distance than any other player.
"Simply, Kevin is a player who only feels good if he leaves everything out there on the pitch," said Nagelsmann of the ex-Dortmund man, whose energy will be required in keeping a tight leash on Witsel.
The Belgium international has proven himself just as pivotal for Dortmund. A crucial, almost irreplaceable link between defence and attack, should Leipzig be looking for the man they need to muzzle to prevent BVB playing, they need look no further than the former Standard Liege, Benfica and Zenit St. Petersburg schemer.
Want proof? A 95 per cent pass completion ratio - over 26 matches this season - is the joint-best in the league. That speaks for itself.
These two could be brothers, at least in a football sense: both are beautifully gifted and supremely versatile.
"He can play in several positions and in several systems," said Dortmund boss Favre of Brandt, who ran the show as BVB easily disposed of derby rivals Schalke in the first game after the restart.
It hasn't been easy for Brandt since his summer move from Leverkusen, but he stepped out of his comfort zone at the BayArena and has given Favre - as the Swiss coach himself admitted - "solutions" in a "3-4-3 that isn't the best system for him, it has to be said."
Brandt has played as a false nine, a winger and even as a defensive midfielder for Favre this season, slotting in where needed by the team at the expense of his stats, which read a modest three goals and six assists in 31 league matches.
Watch: Julian Brandt's Bundesliga Mixtape!
Olmo, who only joined Leipzig in January, already has as many goals this season as his BVB counterpart, but from just 10 Bundesliga appearances.
The Spain international's adaptability has also been exploited by Nagelsmann, but the Leipzig boss himself recognised Olmo's strength is in a central role.
"Before the game, we said that it's important that he plays as a number 10. That is his natural and favorite position," said Nagelsmann after watching the ex-Dinamo Zagreb man score both goals in the 2-0 win at Hoffenheim on Matchday 31.
Watch: Olmo's brace vs. Hoffenheim last weekend!
"We wanted him to be more of a goal threat than in the past few weeks, when he had to do a lot of defensive work. He did well there, but wasn't in front of goal as much as we would like him to."
At least Dortmund will know where to find him.