Madrid, Sep 12 : FC Barcelona striker Robert Lewandowski faces a rapid return to his former club Bayern Munich in a key Champions League tie on Tuesday night. Lewandowski scored a hat-trick in his Champions League debut for Barca at home to Viktoria Plzen last week, but Bayern will be much tougher opponents as they look to continue their recent positive results against Barca. The 8-2 defeat that Bayern inflicted on Barca in August 2020 was traumatic for the Catalan club, as were two 3-0 losses in the group stage last season, which went away to ensuring that Barca failed to qualify for the knockout stage of the competition. After a summer of big spending, it's vital for Barca to make it out of the group this time, and a win in Munich would be a huge step towards assuring that. Barca coach Xavi Hernandez rested key players, such as Lewandowski, Ousmane Dembele and Pedri in their weekend win away to Cadiz, and they are expected to start in the Allianz Arena on Tuesday. Former Bayern legend Karl-Heinz Rummenigge commented in the Spanish newspaper Diario AS that he hopes Bayern fans give Lewandowski a warm welcome on his return. "We shouldn't forget that he played here for eight years, during which time he won everything you can win and scored between 30-50 goals every season. He also joined us for nothing and he went leaving 45 million euros, so he made a big contribution to Bayern," commented Rummenigge. Atletico Madrid are also in action in Germany on Tuesday with a visit to play Leverkusen. After last week's dramatic win at home to Porto, a second win would put Atletico in the driving seat in their group, and Diego Simeone rested Joao Felix, Koke and Marcos Llorente for Tuesday's game, reports Xinhua. Leverkusen kicked off their European campaign with a surprise defeat in Bruges, which leaves them with a lot of work to do if they want to battle with Atletico and Porto for a place in the last 16. /IANS