Five-time Champions League winners Bayern Munich begin their attempt to add to their trophy haul when they face Olympiacos.
Pep Guardiola's men were beaten in the semi-finals of the competition last season by Barcelona, while the Greek side crashed out at the group stage.
Olympiacos
Olympiacos will be looking to fare better in this campaign than they did the last as they exited the tournament at the first hurdle.
The Greek side were drawn with Atletico Madrid, Juventus and Malmo in Group A, and managed to win all of their home matches, including a 3-2 victory over Diego Simeone's men.
However, their three victories were not enough to see them through into the knockout round as Atletico Madrid and Juventus progressed, leaving Olympiacos to settle for a place in the Europa League, where they crashed out in the round of 32.
Olympiacos's best finish in the Champions League was when they managed to reach the quarter-finals of the competition in the 1998-99 campaign, and the club face a major challenge to try to even equal that feat this time around.
Marco Silva's men have earned the chance to have another crack at the Champions League following their triumph in the Greek Super League last season. The team won the league by eight points from their nearest rivals Panathinaikos, losing just four matches over the course of the season.
Olympiacos have enjoyed an impressive start to the new campaign as they have won all three of their league matches so far this season, including their 3-1 victory over Platinias. Silva's side will take a great deal of confidence into their clash against Bayern considering their home record last term.
Recent form: WWW
Bayern Munich
Bayern saw their hopes of securing a sixth title dashed last season by Barcelona as they succumbed to a 5-3 aggregate defeat in their semi-final clash.
Guardiola's men cruised through the group stages last season by winning five out of their six matches, losing only to Manchester City.
The club eased past Shakhtar Donetsk and then overcame a spirited Porto side before they were eventually knocked out by the eventual winners of the competition.
Bayern have a tremendous record in the Champions League over the past four seasons as they have reached at least the semi-finals of the competition in the last four terms, reaching the final twice and winning the tournament in the 2012-13 campaign.
Guardiola will know that a lot will be expected of his side once again as they embark on their bid to add to their trophy haul in the competition, which they earned by winning the Bundesliga last season.
Munich have had an excellent start to their campaign, winning all four of their Bundesliga fixtures and their first-round match in the DFB-Pokal, although they did lose in the DFL–Supercup against Wolfsburg on penalties in August.
Guardiola will be hopeful that his side can take their good form from the league into their Champions League campaign to kickstart their European season.
Recent form: WWWW
Recent form (all competitions): LWWWWW
Team News
Bayern are expected to be without a host of players for the match due to injury, including Javi Martinez, Arjen Robben, Mehdi Benatia, Holger Badstuber, Jan Kirchhoff and Franck Ribery.
Due to their injuries in defence David Alaba could partner Jerome Boateng at centre-back although Philipp Lahm is also an option for Guardiola for the clash.
Thomas Muller, Robert Lewandowski and Douglas Costa are expected to lead the line for Bayern in the absence of Ribery and Robben.
Silva has only one new injury worry to contend with as forward El Fardou Ben Nabouhane is expected to miss the match, and he may opt to name the same team that defeated Platanias at the weekend.
Esteban Cambiasso will start in the defensive midfield role alongside Luka Milivojevic, while Brown Ideye will lead the line in attack, supported by Alejandro Dominguez and Jimmy Durmaz.
Olympiacos possible starting lineup:
Roberto; Elabdellaoui, Da Costa, Siovas, Masuaku; Cambiasso, Milivojevic; Dominguez, Pardo, Durmaz, Ideye
Bayern possible starting lineup:
Neuer; Rafinha, Boateng, Alaba, Lahm; Alonso, Vidal, Thiago; Muller, Costa, Lewandowski
Head To Head
The clubs have met just twice in their histories, which have both come in the Champions League. Bayern have won both meetings, claiming a 3-0 victory in their clash in 1980 at Munich and a 4-2 win in the reverse fixture in Greece.
We say: Olympiacos 1-2 Bayern Munich
Both sides come into the game in excellent form, but Bayern have proven their quality in the competition over the past few years and they have just enough class in their team to overcome the Greek side.