The quarter finals of the Europa League pitches Arsenal against CSKA Moscow, with the Gunners progressing through the last 16 after an impressive 5-1 aggregate win over AC Milan across 2 legs. The Russian giants are a mainstay of European football and always represent a tough fixture - especially when playing them on home turf, which is a challenge that awaits next week. First though, the opening leg at home. In terms of Arsenal's history against the Moscow outfit, it's pretty poor - one draw and one loss. Arsene Wenger and his side will be hoping to rectify this record across the two last 16 ties.So, what have the Gunners got to look out for when it comes to CSKA? Well, the side found their way into the Europa League after they finished third in their Champions league group behind Manchester United and FC Basel. Over the course of that group stage, while they underwhelmed, they did manage to secure an impressive win against Basel in October that helped them on the way to finishing ahead of Benfica - a side they beat on both occasions during the group.It's been a long route to the quarter finals of the Europa League for CSKA. Before they progressed to the group stages of Europe's premier European club competition, they had to make their way through Greek side AEK Athens and Swiss side Young Boys.Finishing the group in 3rd place with 9 points, they joined the last 32 of the Europa League where they were paired with the side that claimed second place in Arsenal's Europa league group, Red Star Belgrade.Belgrade and Moscow had a fiercely competitive fixture over 2 legs, with the tie in Serbia ending goalless and the home leg ending with only a goal from Russian international forward Alan Dzagoev making the difference.If that was a low-scoring affair, it was in sharp contrast to the most recent fixtures - the round of 16 tie with Olympique Lyon. CSKA progressed through to the quarter finals after a 3-3 aggregate draw - losing the tie in Moscow 1-0 but travelling to Lyon and earning a very impressive 3-2 victory in France.The first leg of Arsenal's tie with Viktor Goncharenko Moscow side is taking place in the Emirates Stadium in North London, which means the second and likely decisive leg will be played in Russia, which has often been a difficult place for English sides to travel too.Tactically, having this away fixture second will change the way that Wenger approaches the game. While it is of vital importance that Arsenal lay down a marker in the relative comfort of the Emirates, they will also need to take a defensive approach, as shipping away goals could prove to be very costly.After completing 30 second half minutes - and also winning and scoring a penalty - against Stoke City at the weekend, Alexandre Lacazette is back in contention to lead the line for Arsenal following being sidelined through a knee injury for several weeks. Wenger is still unsure as to whether he will start the game, however, saying in his pre-game press conference: "Lacazette’s still lacking a bit of competitive edge. He’s been out for two months, he worked hard but he still lacks a fraction maybe."With this being the case, and with Pierre-Emerick Aubameyang cup-tied, responsibility may fall once more on the shoulders of Danny Welbeck, who performed well in the previous tie against AC Milan when called upon, but has often been found lacking during his Arsenal career.Also a doubt for the game is goalkeeper Petr Cech, with Wenger saying that, while he has improved, he will likely still be unprepared for Thursday. Whether the Czech stopper would have played anyways is unclear as Wenger has opted for David Ospina thus far in cup competitions.After a 5-1 aggregate victory in the previous leg against AC Milan - including a 2-0 away win in the first leg - the Gunners confidence in the competition is high. In those two games, Arsenal did a good job defensively, while also offering a threat going forward - traits that have not always been seen together in the league. In terms of players that could pose a threat for the Russian side, Ahmed Musa - currently on loan from Leicester City for the remainder of the season - may not have set the Premier League alight, but he has the pace to cause real problems at the back. There's also veteran Russian midfielder Alan Dzagoev pulling the strings in the centre of the field and goalkeeper Igor Akinfeev, who recently put an 11 year Champions League clean sheet drought to bed. The side, who currently sit in 3rd place in their domestic league - just a few points behind city neighbours Spartak Moscow in second and Lokomotiv Moscow in first - are certainly no pushovers. Arsenal appear to be well aware that the Europa League is the only way to go about salvaging something from this season. The player and managers also know this - it was evident from the Milan performance, and it was evident in the first half of Stoke City game - the Europa League has taken on unprecedented importance, and that can all end abruptly if there's a poor result in the first leg. In the general scheme of things, considering the strength of some of the teams left in the competition, drawing CSKA was lucky. If Arsenal want to follow through on their aspirations of lifting the Europa League trophy, they will need to be dominant in home games like this one. The focus for this game must be on getting a good win heading to Moscow and avoiding another difficult situation, as has too often in the past been the case.