Premier League holders Chelsea play Qarabag in Baku, Azerbaijan on Wednesday night seeking to progress from Champions League Group C.
Here, Press Association Sport looks at some of the talking points ahead of the contest.
Taking care of business
Win and Chelsea will be in the knockout stages. Even a draw will be enough if Atletico Madrid drop points against Roma, who enter the fifth round of matches one point better off than Chelsea. Chelsea beat Qarabag 6-0 in September, but the Azerbaijan side have since pushed Roma close and twice drew with Atletico. Chelsea, meanwhile, claimed one point from two games with Roma. Securing a place in the last 16 with one game to spare, even if first can still be contested, will ease Blues' minds.
Consistency required
Since losing 3-0 at Roma, Chelsea have beaten Manchester United 1-0 and West Brom 4-0. The Blues have four straight Premier League wins since the defeat to previously pointless Crystal Palace. Antonio Conte's side have veered from the sublime (at Atletico Madrid) to the spineless (at Palace) this season and must show greater consistency, no matter the occasion or opposition.
Luiz to get a chance?
David Luiz was an integral figure in Chelsea's title triumph in Conte's first season, but his star has fallen this term. Necessity saw the Brazil defender moved forwards into midfield in October's 3-3 draw with Roma, but Conte admitted the experiment saw Chelsea's approach change, for the worse. And after the 3-0 loss in Rome, with Luiz in a crumbling defence, the Brazilian has been a spectator. Not even on the bench against United, he was an unused substitute at West Brom, but he may get his chance in Baku, not least to give the impressive Andreas Christensen a breather.
Baker's dozen of games
Qarabag is the first of 12 games before the end of the calendar year and 13 (a Baker's dozen) if you include the January 3 clash at Arsenal. The congested schedule makes rotation necessary and Saturday's trip to Liverpool may be on Conte's mind when it comes to team selection in Baku. He must get the balance right, though, as Chelsea must maintain momentum. Conte often references that he used just 13 or 14 players when Chelsea had just a domestic focus last season. Now his more peripheral men must show they too can perform.
Morata and Eden are Hazard-ous
At Atletico and again at West Brom, striker Alvaro Morata and forward Eden Hazard showed their understanding. The pair can become a devastating partnership to rival any in the European game - but they must keep producing. With Cesc Fabregas' artistry and N'Golo Kante's industry, Chelsea have players the envy of many of their rivals. It is about their team-mates rising to the occasion, like they did last season.
Source: PA
