Mesut Özil
Mesut Özil has been a key player for Arsenal this season, supplying 12 assists and four goals. Getty Images

Arsenal playmaker Mesut Özil has stressed that keeping a clean sheet is just as important as scoring goals when his side travel take on Olympiakos in Greece on Wednesday, when a place in the last 16 of the Champions League will be on the line. Arsenal go into the game in third place in Group F, three points behind the Greek champions. Because of Olympiakos’ 3-2 victory at the Emirates Stadium earlier in the campaign, Arsenal must not only win at the Karaiskakis Stadium, but do so by two goals, or by a one-goal margin when scoring at least three times.

Arsenal don’t have fond memories of trips to Piraeus, losing on all three of their previous visits, all since 2009. And the meeting in London in September was a further disappointment. Although Arsene Wenger’s team dominated possession and shots on goal, Olympiakos caught them cold from set-pieces and on the counter attack. And Özil has made it clear that his team cannot afford any slip-ups this time around.

“It will be very, very hard,” he told Arsenal’s official website. “Olympiakos can play good football and we saw that at the Emirates. They want to play on the counter-attack but we can’t concede goals like we did before again.

“The fans will be behind them and our goal has to be to beat them. I have played in Greece before. I know that there will be a very good atmosphere, the fans are crazy and they really support their team right through the full 90 minutes. We have to be focused on the game, we have to give a really good performance.”

If Arsenal don’t get the result they need on Tuesday it would be the first time in 16 years that they will have failed to make it into the last 16 of the Champions League. And it would mean dropping into the Europa League in the new year.

Their situation is complicated by a lengthy injury list. Alexis Sánchez and Santi Cazorla have become the latest casualties, joining Francis Coquelin, Jack Wilshere, Mikel Arteta, Danny Welbeck, Tomas Rosicky and David Ospina on the sidelines. On Saturday, a much-changed lineup struggled against Sunderland, before pulling through to record a 3-1 victory and move up to second in the Premier League table. The match also saw some welcome good news on the fitness front with the return off the bench of forward Theo Walcott. And Olympiakos coach Marco Silva is refusing to get overly encouraged by Arsenal’s injury problems.

“I don't care which players are missing from Arsenal,” he said, according to UEFA.com. “We used players for the first time when we went to the Emirates because we had injuries and used young players who had no experience but they wanted to win. Why would this be any different for Arsenal? No matter who is playing, they will play to win. I don't believe Arsenal underestimated us in the first match in London. I think that at this level all matches are quite difficult.”

Olympiakos have no new injury worries, with Colombian forward Felipe Pardo expected to be passed fit. His side have won the Greek Superleague for 17 of the last 19 seasons, and they already look set to improve on that record this season. A 4-3 win over Panthrakikos on Saturday meant the side managed by Portuguese coach Marco Silva extended their perfect start to the campaign in the league to 13 matches. They have been particularly strong at home, where a 3-0 defeat to Bayern Munich in September was their only loss at the Karaiskakis Stadium in the whole of 2015.

Olympiakos will be looking to thwart Arsenal’s charge and claim a place in the Champions League knockout phase for the fourth time. The last time they accomplished that feat was two seasons ago, when they faced Manchester Untied in the Round of 16 and exited despite a goal from then on-loan Arsenal forward Joel Campbell. With so many injuries, the Costa Rican could well be in the Arsenal lineup looking to eliminate Olympiakos on Wednesday.

Probable lineups

Olympiakos
G: Roberto

D: Elabdellaoui, Botía , Siovas, Masuaku

M: Milivojevic, Cambiasso, Kasami

F: Pardo, Ideye, Seba

Arsenal
G: Cech

D: Bellerín , Mertesacker, Koscielny, Monreal

M: Flamini, Ramsey

Campbell, Özil , Oxlade-Chamberlain

F: Giroud

Kickoff time: 2:45 p.m. EST

TV channel: Fox Sports 2

Live stream: Fox Sports Go, Fox Soccer 2Go