2012 champions Chelsea will look to recover from two successive defeats with this fixture, a rematch of last season's Europa League semi-final. On that occasion, the Blues won 5-2 on aggregate and Jose Mourinho's old adversary Rafael Benitez secured their passage to a fourth European title.
Four months later, with both teams back in Uefa's top-level competition, it could be a much tighter affair. Mourinho, a winner with Porto in 2004 and Internazionale in 2010, seems determined that Chelsea avoid an early elimination: "I don't want to win the Europa League. It would be a big disappointment for me."
Blues duo Marco van Ginkel and Kevin De Bruyne could make their Champions League debuts; the other summer arrivals, Andre Schurrle, Samuel Eto'o and Willian, have a combined total of 115 appearances in the competition. Aside from youngsters Thomas Kalas and Kenneth Omeruo, out with long-term injuries, there are no absentees for Chelsea to contend with.
KICK-OFF: Wednesday, 7:45pm
PAST TWO MEETINGS…
Chelsea 3 (Torres, Moses, Luiz), Basel 1 (Salah), Europa League, May 2013
Basel 1 (Schar), Chelsea 2 (Moses, Luiz), Europa League, April 2013
Jose Mourinho has never lost the opening match of a Champions League group, recording seven wins and three draws.
Swiss clubs have only won twice in 30 away matches against English sides.
Fernando Torres scored nine times in European competitions last season, six of them in the Europa League.
Chelsea to win: 1.3
Basel to win: 5.5
TV: Live on Sky Sports 1 at 7:45pm