UEFA Champions League action returned on Tuesday night, but the biggest fixture at this stage of the competition will be the rematch between 2020 finalists Bayern Munich and Paris Saint-Germain on Wednesday.Bayern Munich have continued their impressive form this season and are currently unbeaten in the Champions League. Meanwhile, PSG lost two games in the group stage of the European competition but were commanding in the two-legged Round of 16 fixture against Barcelona.Classic Bayern 🆚 Paris goals...😎 Who's scoring this time? #UCL pic.twitter.com/Hkxa4haq92— UEFA Champions League (@ChampionsLeague) April 5, 2021As one would expect, the Bavarians are the leaders in the Bundesliga. However, their French opponents have surprisingly fallen behind in the race for the Ligue 1 title and are three points behind table-toppers Lille.Bayern Munich vs Paris Saint-Germain: 5 players who will be key in determining the outcome of the matchBayern Munich and PSG have a star-studded lineup, with some of the best players at both ends of the pitch.While Robert Lewandowski is currently out injured, we take a look at the five players from either team who could play key roles in the outcome of this game.#1 Keylor Navas | Paris Saint-GermainKeylor Navas has been in great form for Paris Saint-Germain in the UEFA Champions LeagueKeylor Navas is a veteran in the UEFA Champions League. During his spell with Real Madrid, he helped the club lift three back-to-back titles between 2016 and 108, though much of the spotlight was on the charismatic Cristiano Ronaldo.The shot-stopper has consistently produced some amazing reflex saves to rescue PSG. Despite being 34, he is one of the most athletic goalkeepers in Europe at the moment.Keylor Navas owned Barcelona 🔒pic.twitter.com/0Lci5Lq7bN— Goal (@goal) March 16, 2021Navas was a brick wall against Barcelona in the second leg of their last 16 tie and blocked as many as eight shots in the first half itself. His save to deny Lionel Messi from the penalty spot proved to be the turning spot in that game.He was rightly awarded the Man-of-the-Match award after his inspiring performance. His experience in the knockout stages of the competition will come in handy against Bayern Munich.#2 Thomas Muller | Bayern MunichThomas Muller will have to lead the Bayern Munich attacking line in the absence of Robert LewandowskiThomas Muller will be without his partner-in-crime, Robert Lewandowski, on Wednesday. The absence of the prolific striker puts additional responsibility on the Raumdeuter's shoulders, as he is expected to not only create chances but finish them too.Muller has 15 assists in the Bundesliga this term and with nine games to go, he can surpass his own record of 21 assists in a single campaign.While he only has three assists to his name in the Champions League, he can always create something out of nothing to provide his teammates with goalscoring chances.Thomas Müller has now provided exactly twice the number of assists as he has scored goals for Bayern across the past two Bundesliga seasons:⚽️ 18 goals🅰️ 36 assistsThe evolution into one of Europe's top creators is complete. pic.twitter.com/M8v20z2cZU— Squawka Football (@Squawka) April 3, 2021Paris Saint-Germain have been solid defensively this season and have a fully fit back four heading into the game. Muller will have to make use of all of his skills and experience to break the dogged PSG backline.Also See: The 10 highest-paid goalkeepers in the world