Having topped the Bundesliga in December, Leverkusen are now five points adrift of the Champions League places in sixth after winning just one of their last six games. For Peter Bosz's team, who crashed out of the Europa League on Thursday, a promising season is now beginning to fall apart.
"There are always setbacks in life -- the question is how you turn things around," a dejected Bosz told Sky.
After a dominant first-half performance from Leverkusen, Freiburg launched a smash-and-grab attack to take the lead just after half-time. With a darting run into the box, Hoeler cut the ball back to an unmarked Ermedin Demirovic, who swept it past debutant goalkeeper Lennart Grill. Hoeler doubled the lead 10 minutes later, tapping the ball in after a sharp cross from Vincenzo Grifo.
"We had a bit of luck in the first half, but we said in the break that we wanted to take the game to them," Hoeler told Sky.
Jamaica winger Leon Bailey pulled a goal back 20 minutes from time, but Freiburg held on to condemn Leverkusen to their eighth defeat in all competitions in 2021.
A howler from goalkeeper Robin Zentner condemned Mainz to a 1-0 defeat at home to Augsburg and kept the relegation-threatened side in the bottom two.
With 25 minutes gone, Zentner mistakenly passed the ball straight to Augsburg's Florian Niederlechner, despite being under no pressure. Niederlechner gratefully squared the ball to Andre Hahn, who slotted it into the empty net to take Augsburg eight points clear of the drop zone.
"Robin is old enough to put it behind him. He's helped us out enough times in the past," said Mainz coach Bo Svensson, defending his goalkeeper.
Standout matches today