Julian Nagelsmann insists the outcome will not decide anything, but RB Leipzig's trip to Bayern Munich is undoubtedly a pivotal moment in the Bundesliga title race.

A charging Bayern squad suddenly sit on top of the table, a point clear of their opponents. The reigning champions have hit top form, reeling off six league wins on the spin. They have scored 12 goals in their three outings since the mid-season break, too.

In contrast, Leipzig - who have enjoyed such a rapid rise since they were formed in 2009 - have stumbled in recent weeks.

A 2-0 defeat at Eintracht Frankfurt was followed by a 2-2 draw at home to Borussia Monchengladbach last time out. Sunday's trip to the Allianz Arena should tell us a lot more about their prospects of lasting the distance.

With help from Opta, we look at key statistics behind both teams' recent performances - and identify how a coaching change may turn out to be crucial in the final reckoning.

Leipzig out of luck, or are they wilting under pressure?

Vibrant, youthful, exciting – set aside the off-field politics that surrounds Leipzig's ownership, and there is little to dislike about them on the pitch.

But since the post-winter break, Leipzig have relinquished their position at the Bundesliga's summit and won just once in four matches across all competitions. If they weren't hopeful of a title challenge this could be dismissed as a blip, but given their lofty ambitions, it warrants investigation.

Even with the in-form Timo Werner, Leipzig have been far less impressive in front of goal. Before the break they had scored 67 times but their expected goals (xG) was 62 – since returning they've netted six times, which corresponds exactly with xG.

They're averaging more shots now, 18.5 per game as opposed to 16.5 before Christmas, but accuracy has dropped to 49 per cent from 59, while big-chance conversion has decreased spectacularly from 41 per cent to just 17.

Leipzig are still creating chances at an almost identical rate, so the data suggests a decrease in composure is to blame for their issues.

Demme departure a factor

It was always likely to be a blow to lose club captain Diego Demme, the tidy and tenacious midfielder Leipzig allowed to join Napoli in the January transfer window.

Given he is more of a defensive-minded player, it's difficult to attach too much importance to his absence from an attacking perspective, but even the smallest change can have a ripple effect – after all, Leipzig averaged 2.9 goals per match with him in the starting XI and just 1.7 without him.

Their win percentage also takes a dip from 65 to 44.4 per cent when Demme has not been in the line-up.

They averaged 2.2 points each match when the German started, but that plummets to 1.6 if he has been absent.

Bayern back in business

For a time in the first half of the season, it seemed possible we could be in for a Bundesliga title race without Bayern. However, last season provided a cautionary tale.

Bayern eventually came good in the 2018-19 campaign, finishing strongly enough to win the title by two points despite Borussia Dortmund – who ended up second – holding a nine-point lead over them at the end of the 15th matchday.

Statistically, there were only negligible differences between how Bayern performed before and after last season's winter break, but this term there are notable improvements, even if there is a smaller sample of games to look at post-break.

Big-chance conversion is up from 40 per cent to 53; shooting accuracy is now 64 per cent when it was 51; they're averaging four goals per game compared to 2.8 and conceding one every match, as opposed to 1.2.

Whereas last season Bayern appeared to simply profit off Dortmund's collapse, this term there is early evidence of genuine improvement.

With that coming off the back of several uninterrupted weeks of working with their new coach, Hansi Flick, it seems a leadership change might be paying dividends.