Union Berlin failed to reclaim their spot atop the Bundesliga table after being thrashed 5-0 at Bayer Leverkusen on Sunday.
Union, who have been at the summit of the Bundesliga ladder since early September, conceded five second-half goals as Leverkusen produced their best performance under manager Xabi Alonso.
After a goalless first half, the game burst into life, with former Union midfielder Robert Andrich tapping in a corner to give the home side the lead.
With Union pushing forward looking to re-live the heroics of last week's comeback win over Borussia Moenchengladbach, Leverkusen's French forward Moussa Diaby hit the visitors twice on the counter in less than sixty seconds - pushing his side's lead out to 3-0 after just 58 minutes.
Czech striker Adam Hlozek scored his first Bundesliga goal since arriving from Sparta Prague in the summer to make it 4-0, before Mitchell Bakker added a fifth late to round out a resounding home win.
Going into the match, Union had conceded just nine league goals in 12 games this season - but conceded more than half of that figure in just 30 minutes.
The loss was just the third of the season for Bundesliga surprise packets Union, while Leverkusen's victory was also their third in a disappointing campaign.
In Sunday's late game, Freiburg have the chance to jump up to second spot when they host Cologne.
