At the halfway stage of the group campaign, the two clubs are well placed to progress though the fortunes of Manchester United and Tottenham were dented last time out.
Here, Press Association Sport runs the rule over what we might expect from the midweek fixtures.
City and Liverpool Lead the Way
The two teams are battling for supremacy in the Premier League and sent a warning to their European rivals in their last outings by brushing aside lesser opposition in commanding fashion.
City ran out 3-0 winners at Shakhtar Donetsk to move to the summit of Group E while Liverpool put four past Red Star Belgrade to go top of Group C.
It is difficult to envisage anything other than the two English sides enhancing their points total and goal difference in the return fixtures.
Can United Summon Spirit of ’99?
Jose Mourinho made no attempt to disguise his aim of finishing second in Group H—in effect conceding that United could not compete with Juventus, who outclassed the Red Devils at Old Trafford a fortnight ago.
The Turin return seems like damage limitation for a side that is earning a reputation for starting sluggishly but they could do worse than look to the side that famously prevailed against the odds in 1999, despite falling two goals down inside the opening quarter of an hour.
Tottenham in Last Chance Saloon
Tottenham’s frustrating tendency to concede late on has cost them dearly in Group B, denying them a potentially priceless draw at Inter Milan in their opener and a win against PSV Eindhoven a couple of weeks ago.
One point from three games leaves Mauricio Pochettino’s side in a precarious position and another false step is likely to spell the end of their Champions League adventure for another season, at least.
When PSV visit Wembley for the return fixture, Spurs simply have to win.
Should Messi Be Returning so Soon?
The news that Lionel Messi had fractured his arm and would face a period on the sidelines was seen as a boost to Barcelona’s rivals but the Catalan club have won all four of their fixtures in his absence.
The Argentinian has been named in the squad which will travel to Inter Milan despite not yet having the “medical all-clear”—and though it is obvious Barcelona are desperate for the return of their talisman, they should be cautious of rushing him back.