The French champions, Lyon, will start as slight favourites when they travel to take on Denizlispor in their third-round first leg tie tonight.
Paul Le Guen's side were one of the eight teams to gain a second crack at European competition after bowing out of the Champions' League at the first group stage.
But trips to Turkey are rarely easy and Denizlispor, who currently lie ninth in their domestic league, are sure to be charged up for the first leg of the third-round tie.
Denizlispor have already faced French opposition this season after overcoming Lorient in the first round, and Le Guen is keen to avoid following them out of the competition. "We are going to play a difficult game on a pitch which will be awkward as the Lorient match proved," he said. "Denizlispor are a very aggressive side, in a good way, and we will have to be more determined than ever."
The visitors will be without their main striker Sonny Anderson who has a groin injury, while the defender Jérémie Bréchet is still recovering from a sprained knee he picked up on international duty with France last week. Sidney Govou is back, however, as are the Brazilian internationals Edmilson and Juninho.
Wisla Krakow will go all-out for a win in the first leg of their tie against Schalke 04 as their coach Henryk Kasperczak does not fancy their chances in Germany.
"They are well-organised and disciplined," Kasperczak said. "We need to get a result in the first game, not losing a goal and scoring at least one."
Schalke, fifth in the Bundesliga, have a fitness worry over the German international striker Gerald Asamoah who suffered a gashed leg in training. They are also without Victor Agali, who has a knee problem, and Andreas Möller, who injured a foot in training.
Ukraine's Dynamo Kiev, knocked out of the Champions' League by Newcastle United, relaunch their European campaign in Turkey at Besiktas. Greece's Panathinaikos, who ousted the Prague clubs Slavia and Sparta on their way to the Champions' League quarter-finals last season, aim to continue their mastery of Czech opposition when they travel to Slovan Liberec.