FC Barcelona's Lionel Messi, top, duels for the ball against Real Sociedad's goalkeeper Claudio Bravo during a Spanish La Liga soccer match at the Camp Nou stadium in Barcelona, Spain, Saturday, Feb. 4, 2012. (AP Photo/Manu Fernandez)
Andre Schurrle, F, Bayer Leverkusen
Schurrle has to reach the heights of last season when he scored 15 goals in 33 Bundesliga appearances for unfashionable Mainz, but his all-round play, searing speed and powerful right foot make him a threat to any team. Hasn't scored since the start of November so question marks hang over his ability to step up thrive in higher-profile team, but national team coach Joachim Low has been impressed enough to make him a regular for Germany. In the absence of the injured duo Sidney Sam and top scorer Eren Derdiyok, Schurrle will be expected to lead the line with Stefan Kiessling.
Lars Bender, M, Bayer Leverkusen
The midfielder, twin brother of Borussia Dortmund's Sven, broke into the national side last November. Much will be expected of Bender, with Michael Ballack missing the game through an injury he picked up in a training session. Has chipped in with three goals this season, including the winner against Mainz last month, and also scored his first CL goal in the 2-0 victory over Genk back in September. Bender possesses great touch, passes accurately and has the boundless energy that you'd expect from a player in his early 20s. Still, he could find himself chasing shadows against a side with the quality of Pep Guardiola's Barcelona.
Lionel Messi, F, Barcelona
What more can be said about probably the world's greatest ever player? The three time Ballon d'Or winner already has 29 goals from 26 appearances this season in La Liga and Champions League. That haul includes four hat-tricks, although incredibly the Argentine masetro is still lagging behind Real Madrid's Cristiano Ronaldo on Spain's scoring chart. What makes Messi so special is his ability to burst away from defenders off either foot, his balance, pace and range of skills. Messi is also a selfless team player, as his terrific assist record testifies.
Alexis Sanchez, F, Barcelona
The Chile international is still working his way back to health following an injury plagued first half-season with Barcelona, but the signs are good that he will show why the European champions splashed out a cool $47 million for the Udinese winger. Sanchez tore his hamstring against Real Sociedad in September and was out for action for nearly two months. A two-week absence in January followed after he sustained a shoulder injury during the 2-2 draw against Real Madrid in the Copa del Rey. Barca boss Pep Guardiola is treating Sanchez with kid gloves at the moment, but his goalscoring record in recent games has been outsanding. Carrying a return of eight goals from nine games into Tuesday's match, Sanchez will one to watch.
Xavi Hernandez, M, Barcelona
A wonderful player who will pass teams to death given the opportunity. He's usually the man to produce the defence-splitting pass and weighs in with his fair share of goals, too. Now in his 14th season with the Catalans, Xavi is also an expert free-kick taker. Put the ball 30 yards out in a central position and there is usually only one result. In partnership with Andres Iniesta, the pair form the midfield axis from which most of Barca's best work stems.
Lisandro Lopez, F, Lyon
The Argentine was the man to replace Karim Benzema when the striker joined Real Madrid in 2009, and he has not disappointed. Lyon paid Porto €24 million for the attacker, who can also operate on the wing. Lopez got back on the goal trail to no avail on Saturday when he scored a late penalty in the shock 2-1 home defeat by Caen. Possessing boundless energy and a lethal right foot, Licha's clinical finishing has established himself as a fans' favorite at Stade de Gerland. He was linked with a move to Liverpool in October 2010 as a possble replacement for Fernando Torres.
Bafetimbi Gomis, F, Lyon
The striker is one of the main reasons Lyon booked its place in the knockout stage. He four goals in a 7-1 victory at Dynamo Kiev in the final group game which, coupled with Ajax's home defeat to Real Madrid, sent the French club into the knockout round. His feat also led to the quickest European Cup/Champions League hat trick in history. Lyon's league form has been patchy of late but with Gomis up front (14 goals this season) they should have too much class for the Cypriot minnows.
Hugo Lloris, G, Lyon
Ligue 1's goalkeeper of the year for the last two seasons, Lloris' reputation extends far beyond France, with some considering the French international among the world's best at his position. His world class reflexes have led to some spectacular shows for a Lyon side that has perennially found itself at this stage of Champions League. Against APOEL he is unlikely to be tested often, but with the Cypriots relying on counter attacking soccer, his ability to react to a quickly developing attack will be tested.
Ailton, F, APOEL
The upstart Cypriots have relied on their 27-year-old Brazilian, who scored seven goals in this year's Champions League. Last year's Cypriot first division most valuable player, Ailton spent most of his soccer career in Scandinavia before a summer 2010 move to the Mediterrainen. His clubs have won domestic titles in each of his last three seasons.
Marcelo Oliviera, D, APOEL
One of four APOEL players to appear in all six Champions League group stages, the veteran Brazilian has made his impact felt in his first season in Cyprus, having moved from Greece last summer. For the Cypriots, he's provided to be an adept passer out of the back, competely more than 20 passes per match at near an 80 percent clip. Against Lyon, however, is biggest contributions will have to come without the ball as he and partner Paulo Jorge are matched against Gomis and Lopez.