MONACO — Leipzig sent Monaco crashing out of the Champions League with a 4-1 victory, capitalizing on a comedy of errors in a first-half horror show from last season’s semifinalists on Tuesday.

The visiting German side led 2-0 after just nine minutes, with Monaco’s Jemerson at fault in both goals. The Brazilian defender beat his own ‘keeper with an own goal and set up Leipzig’s second with a feeble pass from the back that Kevin Kampl pounced on to set up Timo Werner to score.

Monaco was a mere shadow of the force that knocked out Manchester City and Borussia Dortmund on its surprise run to the final four last season. Its miserable campaign this season, shipping nine goals in three group-stage losses at home, laid bare the cost of allowing Kylian Mbappe to move to Paris Saint-Germain and the loss of Bernardo Silva, who won with Manchester City against Feyenoord on Tuesday.

But Monaco’s short-termism didn’t completely excuse the players’ gaffes and feeble effort against Leipzig. Downcast Monaco defender Andrea Raggi apologized to fans but said highs and lows are all part of football.

“We live magnificent moments and difficult moments like this,” he told broadcaster BeIN.

The heavy defeat left Monaco coach Leonardo Jardim the uphill task of having to regroup and rally his team for the visit on Sunday of Ligue 1 leader Paris Saint-Germain. Defending champion Monaco already trails PSG by six points ahead of that top-two clash.

Monaco captain Radamel Falcao made the principality side’s bad start against Leipzig even worse by conceding a penalty that Werner converted for 3-0 after 31 minutes.

Falcao made amends with a headed goal in the closing minutes of the half.

But Leipzig’s fourth goal moments later from Naby Keita, who easily wriggled past Monaco defender Kamil Glik, extinguished the short-lived glimmer of hope for the home fans.

The forgettable second half saw Leipzig happy to defend against a toothless Monaco shorn of ideas and ambition.

With Monaco eliminated, Leipzig and Porto will fight for the last qualifying spot in Group G in the final round of group-stage matches.

Besiktas, which drew with Porto 1-1 on Tuesday, has already advanced to the last 16 as top of the group.

Besiktas travels to Leipzig on Dec. 6, with Porto hosting Monaco.