As written above, Basel were certain to finish top of the section before matchday six. For the last match in the group stage Basel had to travel to the INEA Stadion in Poznań. Lech Poznań had already lost to Basel three times this season and only a win would have given them any chance of making it through Group I. Unable to play were defenders Manuel Akanji, Philipp Degen and Daniel Høegh (all due to injury), as well as Marek Suchý, who was out suspended. Walter Samuel made his 100th UEFA club competition appearance playing this match. Reserve goalkeeper Germano Vailati was again Basel's starter because of first choice goalkeeper Tomáš Vaclík's injury. In the 44th minute, Vailati himself also suffered an injury as he played a long pass forward. Just before half-time, third-choice goalkeeper Mirko Salvi was introduced and made his professional debut for the club. Adonis Ajeti also made his debut for the club after coming on as a substitute at half-time in place of Michael Lang. Jean-Paul Boëtius scored the only goal five minutes after half-time, it was his first goal for the Swiss champions. Because Basel ended this stage as group winners, they continued (seeded in the draw) in the knockout phase, which started in February 2016. The draw for the round of 32 was held on 14 December 2015, where Basel were drawn against French side Saint-Étienne. The first leg was played on 18 February at 19:00 and the return leg in the St. Jakob-Park played on 25 February 2016 at 21:05. The first leg of the round of 32 was played in the Stade Geoffroy-Guichard, but without Basel supporters due to the high security alert following the terror attacks in Paris two months earlier. Basel came back from 2–0 down but ended up losing. Moustapha Sall in the fifth minute and Kévin Monnet-Paquet in the 39th minute put the hosts 2–0 in the lead. Then Walter Samuel started Basel's fight-back just before half-time in the 44th minute, becoming the second-oldest scorer in the UEFA Europa League at age 37 years and 332 days; he is surpassed only by Molde FK's Daniel Hestad, who scored at age 40 years and 98 days in this season's group stage.