Rangers. The teams meet for their Europa League second leg on Thursday, with the Germans holding a 3-1 lead from the game at Ibrox in March.
Perhaps unusually, Leverkusen have opted not to play any warm-up friendlies, with their only action coming in intra-squad games.
That means they've been without a match since the end of the Bundesliga season, but Voller doesn't think that will make too much difference.He said: "This is no advantage or disadvantage to not having played any games.
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