One of the great difficulties Bundesliga teams have recently faced is juggling the burden of playing in the Champions League with their ordinary domestic obligations.
A lack of squad depth can have calamitous results. Schalke, for example, reached the 2011 Champions League semifinals but on the domestic front finished just four points above the relegation zone.
Leverkusen last competed in the 2011-12 Champions League, and it was no surprise when they just missed the cut-off for a return to European football's greatest international club tournament a year later.
Things are looking better for Leverkusen this season, however. Despite losing key starters Andre Schurrle and Daniel Carvajal, as well as squad players like Daniel Schwaab, Michal Kadlec and Hajime Hosogai, the Werkself reinforced their starting lineup with the capture of Son Heung-Min, Emir Spahic and Giulio Donati, and added depth in the form of Can and Robbie Kruse.
The signing of Spahic has left B04 with three international-calibre centre-backs in the form of him, Omer Toprak and Philipp Wollscheid. Can is an inspired signing who can play in midfield and across the back four, and at 19 years of age will only get better.
Levin Oztunali, who made his Bundesliga debut in the first matchday following an impressive preseason, is already a serious contender for minutes despite being just 17 years of age. Also in midfield, Leverkusen have the versatile Dominik Kohr, who has been awarded the bronze Fritz Walter Medal in each of the last two seasons.
In defense, recent signing Konstantinos Stafylidis is, at 19, already a capped Greece international. And up front, Arkadiusz Milik has been prolific for Poland's under-21s and had more goals (5) than appearances (4) for Leverkusen's reserves last season.
All of these young players have considerable potential to play a role in Leverkusen's campaign, meaning less stress for the likes of Stefan Kiessling and Lars Bender.