Sami Hyypia's men sit third in the Bundesliga but will want a turnaround in European fortunes, whereas the visitors are in woeful form all roundBayer Leverkusen and Real Sociedad will be seeking their first Champions League points of the season when they meet on Wednesday.
The Liga outfit were beaten 2-0 by Shakhtar Donetsk in their group stage opener, while Leverkusen went down 4-2 against Premier League champions Manchester United.
However, the Bundesliga side have won all three matches in the league since their defeat at Old Trafford, scoring eight goals and conceding just once in the process.
Sami Hyypia's side sit third in the German top flight after their 2-0 win over Hannover on Saturday and face champions Bayern Munich on Saturday.
Leverkusen have enjoyed 100 per cent records in the group stages of the competition in their past two campaigns, though Hyypia has admitted he is unsure whether he will rotate his squad for the clash with Jagoba Arrasate's men.
Sociedad have never recorded a European win on German soil, losing two and drawing one of their three encounters in the country.
Arrasate's charges have not won since their Champions League qualifier against Olympique Lyonnais in August, losing two and drawing three of their last five league games.
Xabi Prieto is unlikely to feature for the visitors, having suffered a thigh tear in his side's 4-1 defeat against Barcelona, while loanee Esteban Granero will miss out.
The midfielder suffered an anterior cruciate ligament injury during the defeat against Shakhtar.
In what will be the sides' first meeting, defeat would see the losers cast three points adrift at the bottom of Group A.
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