The French side delighted their fans by finishing second in Ligue 1 last year, in the process ending an eight-year exile from Europe's premier competition.
But the hope that greeted their achievement has been extinguished by an off-season of discontent.
Following the departure of James Rodriguez to Real Madrid, Monaco's supporters were left frustrated again as Radamel Falcao joined Manchester United in a deadline-day loan switch.
As if off-field issues were not bad enough, the club have also endured a miserable start on the pitch, picking up a mere four points from five games - including three defeats - under new head coach Leonardo Jardim.
Things, therefore, do not look rosy as Monaco begin their Group C campaign with Tuesday's visit of Leverkusen.
However, they will have a striker determined to make an impact in Dimitar Berbatov, who launched his career by scoring 68 times in 154 Bundesliga games for Leverkusen.
The Germans will be hindered by the absence of centre-back Kyriakos Papadopoulos, who dislocated his shoulder in training, while Simon Rolfes and Julian Brandt have missed out recently due to ankle injuries.
However, there is no doubt they enter the fixture with the kind of confidence that is in stark contrast to their opponents.
Indeed, Leverkusen have made a flying start to this term under new coach Roger Schmidt, with five successive wins preceding Friday's 3-3 Bundesliga draw with Werder Bremen.
Included in that quintet of triumphs were 3-2 and 4-0 scorelines against Copenhagen in the third qualifying round.
Leverkusen have enjoyed a rich vein of goalscoring form during those games, finding the net a total of 22 times.
Stefan Kiessling has shone in racking up nine goals, although five did come in a 6-0 thumping of minnows SV Alemannia Waldalgesheim in the DFB-Pokal first round.
The German side endured a mixed Champions League last time out, picking up their biggest win in the competition when beating Shakhtar 4-0 but also slipping to their largest defeat as they were hammered 5-0 by Manchester United.
But Leverkusen did still manage to reach the second round, where they were beaten 6-1 on aggregate by Paris Saint-Germain.
Monaco and Leverkusen have previously met in the 1997-98 group phase.
The French side emerged victorious in the home fixture, winning 4-0, but drew 2-2 on the road.
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