Unheralded high-flyers Union Berlin nipped past Freiburg into second in the Bundesliga on Wednesday as Xabi Alonso's Bayer Leverkusen continued their upwardly mobile trajectory since the 2010 World Cup winner's arrival as manager last month.

Union relinquished a lead they had held since September at the weekend after a lopsided loss to Leverkusen, with Bayern Munich resuming their customary place at the head of the Bundesliga table.

But a 2-2 draw with Augsburg coupled with Freiburg's 3-1 loss at RB Leipzig saw them back into second on goal difference ahead of their last run out before the World Cup hiatus next weekend - against Freiburg.

Union's Dutch-Surinamese forward Sheraldo Becker has played a pivotal role in the side's table-storming form.

And he secured Union's early opener only for Florian Niederlechner to level a minute later.

Kevin Behrens had Union back in front but Niederlechner struck again as half-time approached for the draw.

Freiburg, who were the unbeaten table-toppers of their Europa League group, came unstuck at Leipzig, with Christopher Nkunku on the scoresheet for the visitors. He leads the Bundesliga scoring charts on 12 goals.

In the evening's early kick-off Alonso's Leverkusen followed up their weekend demolition of Union with a come-from-behind 2-1 win in the Rhine derby at Cologne.

Cologne took the lead on the half-hour through an unlikely source - Benno Schmitz.

A spectacular strike - "hang it in the Louvre" the club tweeted - was the defender's first goal in 100 matches for the club, and his first since 2014.

Nadiem Amiri levelled for Leverkusen on 65 minutes from a deflected free-kick with French forward Moussa Diaby, author of a quick-fire double in Sunday's 5-0 rout of Union, securing the victory minutes later.

This fourth success of the campaign lifted Alonso's side up to 13th, two points behind Cologne.

"We all agreed that we were not playing good enough to compete at this level," said Alonso, the former Liverpool, Bayern Munich and Real Madrid midfielder.

"Second half - the energy, the intensity, the desire was there," added the 2010 World Cup winner with Spain who took up his debut first-team coaching job last month with Leverkusen one off the foot of the table.

Elsewhere, Eintracht Frankfurt beat Hoffenheim 4-2 and Schalke edged Mainz 1-0.

With this weekend's programme of matches the last of 2022 it is Bayern Munich, who routed Werder Bremen 6-1 on Tuesday, who will go into the new year as league leaders with an unassailable four-point lead before their closing match of the year against Schalke on Saturday.