Didier Drogba and Chelsea need a win or a scoreless draw against Valencia to reach the round of 16. (Graham Stuart/AFP/Getty Images)

A Group E clash between Chelsea and Valencia sets up as the day’s most intriguing contest with the winner claiming second place behind Bayer Leverkusen and moving through to the knockout rounds.

Here’s a look at what’s at stake in the rest of Tuesday’s matches...

(All matches kickoff at 2:45 EST)

Group E

Advanced: Bayer Leverkusen (group winners)

Advance with a win: Chelsea, Valencia

• Valencia vs. Chelsea at Stamford Bridge

— To control its own fate, Chelsea must claim victory. A 0-0 draw could get them through but not if Genk gets past Bayer Leverkusen at home. Chelsea has never failed to reach the knockout stages of the Champions League and 34-year-old manager Andre Villas-Boas does not want to be the first boss to earn the dubious honor.

• Bayer Leverkusen vs. Racing Genk at Cristal Arena

Jeremy Morel, right, and Marseille will look to punch their ticket to the round of 16 with a win at Borussia Dortmund. (Claude Paris/AP)

Advanced: Arsenal (group winners)

Advance with a win: Marseille

Advance with a win and help: Olympiakos, Borussia Dortmund

• Marseille vs. Borussia Dortmund at Signal Iduna Park

Marseille is through with a win or a draw and an Olympiakos loss to Arsenal. Borussia Dortmund needs an offensive explosion (a five-goal victory margin) and a loss from Olympiakos to sneak into the final 16.

• Arsenal vs. Olympiakos at Karaiskaki Stadium

— The Gunners avoided some drama for a change, wrapping up the group early and enabling themselves to coast through Tuesday’s final group state match in Piraeus, Greece. With Arsene Wenger resting his big guns, Olympiakos will try to top Marseille’s result to advance.

Group G

Advanced: APOEL

Advance with a win: Zenit, Porto

• Shakhtar Donetsk vs. APOEL Nicosia at Neo GSP Stadium

— A victory for APOEL Nicosia will send the home side through as group winners and send their Cypriot supporters into a frenzy. They will become the first team from Cyprus to advance in the Champions League.

• Zenit St. Petersburg vs. FC Porto at Estadio do Dragao

— After beating Porto 3-1 at home, Zenit will advance for the first time with a draw. Meanwhile, the Portugese side must win to advance.

Group H

Advanced: Barcelona (group winners), AC Milan

• BATE Borisov vs. Barcelona at Camp Nou

— Barcelona’s young talent will get a chance to show what’s in the pipeline for the Spanish powerhouse as the team rests Messi, Xavi, Iniesta and others ahead of next weekend’s match against Real Madrid.

• AC Milan vs. Viktoria Plzen at Synot Tip Arena

— Vikrotia cannot advance in the tournament but a draw would earn them a spot in the final 32 of the Europa League. That could be a tall task for a team that has never beaten the Rossoneri.

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