The spotlight in tonight's Champions League quarter-final second legs will be focused on two figures who clashed badly during their time at Barcelona and now find themselves on the brink of elimination from Europe's biggest competition.
One, Paris Saint-Germain striker Zlatan Ibrahimovic, has the opportunity to inflict some kind of revenge on the Catalan club where his career turned sour as his side visit the Camp Nou hoping to overhaul a 3-1 first leg deficit.
The other, Pep Guardiola, will be hoping that his Bayern Munich team can also overturn a 3-1 deficit against Porto and avoid what would be seen as an embarrassing exit, especially if his old charges progress to the semi-finals.
Subscribe to The Week
Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.
The Swedish striker joined Barcelona in 2009 but stayed for just one season. He may have cost Barcelona almost £50m, but it was soon clear that he and then manager Guardiola were not cut from the same cloth.
Since his brief stint in Barcelona Ibrahimovic has made it clear just how frustrated he was during his season under Guardiola. He once described his time at the Camp Nou as "like being back at school", and expressed surprise at the manner in which the players were expected to carry themselves.
The Swede also felt marginalised tactically as Guardiola refused to deviate from his tiki-taka passing system. Barcelona are more pragmatic these days, with the likes of Neymar offering the kind of alternative in attack that Ibrahimovic never had the chance to provide.
"Helping the French champions avoid Champions League elimination at the hands of Barcelona on Tuesday night should be a bridge too far even for him," writes Andy Brassell of Bleacher Report. "But his return to Camp Nou should provoke renewed reflection at a club not always known for its transfer market savvy in recent years.
"His failed transfer... asks many questions of Barca in their most glorious period," he adds. Barca fans "might even afford themselves a thought of what might have been when PSG's captain takes the field".
The Spanish coach whose post-Ibrahimovic Barcelona team is regarded as one of the greatest ever, is now in charge of Bayern Munich. But the team he inherited a season after they humiliated the remains of his Barcelona side 7-0 over two legs in 2013 are now in danger of being eliminated by relative minnows Porto.
The German Bundesliga could be won this weekend, but if Bayern are no longer in Europe the celebrations in Munich will be muted and the inquest will "rumble on all summer", writes Matt Hughes in The Times.
When the former Barcelona coach took over Bayern were reigning European champions and appeared to have taken football to a new level. But last season they were beaten 5-0 over two legs by Real Madrid and now they face an even more embarrassing elimination.
Guardiola's efforts to blame injuries for Bayern's problems led last week to the resignation of the club doctor, Wilhelm Muller-Wohlfahrt, after 37 years and also prompted "the first serious questioning of Guardiola's future", says Hughes.
Guardiola has dismissed talk that he will leave his post at the end of the season, even though he is wanted by Manchester City, but Hughes says he knows that at Bayern "European success a prerequisite rather than an aspiration".
Continue reading for free
We hope you're enjoying The Week's refreshingly open-minded journalism.
Subscribed to The Week? Register your account with the same email as your subscription.