Back in August, when Bayern Munich, Manchester City and Napoli were drawn into the same Champions League group, a chorus of gasps went up inside the auditorium in Monaco.
Three months later, Bayern are nearly sure of advancing, Villarreal has been eliminated and Tuesday's match between City and Napoli will likely determine the second squad that goes through to the next round.
Bayern lead Group A with 10 points, followed by City with seven and Napoli with five.
City can advance with a win, while Napoli need to beat the Premier League leaders to revive their chances.
After beating Newcastle 3-1 Saturday to maintain their five-point lead over Manchester United in England, City come to Naples with a nine-match winning streak in all competitions - with a whopping 33 goals over that span.
Still, City manager Roberto Mancini sees room for improvement.
"I know that we can find more in Naples," the Italian said after the Newcastle match. "Napoli this season are playing very well at home. If we want to win in Naples, we should play better than we did this afternoon.
"The atmosphere will be fantastic and it will be a very difficult game," added Mancini, who knows a thing or two about playing in Naples from his time as a Serie A player and manager with Fiorentina, Lazio and Inter Milan.
Boosted by some of the most rabid fans in Italy, Napoli are unbeaten at home in 10 matches since returning to Europe after a 13-year absence in 2008. The last foreign team to prevail at the San Paolo Stadium was Eintracht Frankfurt in December 1994.
And City couldn't beat Napoli at home, needing a late goal from Aleksandar Kolarov to rescue a 1-1 draw after Edinson Cavani had given Napoli the lead in September.
Napoli have won just one of their last seven matches in all competitions but will want to build off an impressive second half in the 3-2 loss to Bayern earlier this month.
"This squad is going through a growth phase and we're getting used to dealing with the double challenge of Serie A and the Champions League," Napoli coach Walter Mazzarri said.
Both sides are fully healthy and have a range of weapons in attack.
Bankrolled by Abu Dhabi owners who have splashed more than $1 billion on the club since their takeover in 2008, City forwards Sergio Aguero, Edin Dzeko and Mario Balotelli have already scored a combined 26 goals in the Premier League this season.
Aguero is the son-in-law of Diego Maradona, who led Napoli to Italian titles in 1987 and 1990.
Napoli rely on their "Three Tenors" of Cavani, Ezequiel Lavezzi and Marek Hamsik - who combined for 43 goals in Serie A last season.
David Silva, Dzeko, Kolarov and Gareth Barry were all on the bench against Newcastle so they are likely to start. Napoli midfielder Juan Zuniga is suspended, while captain Paolo Cannavaro will return from a one-match suspension.
Meanwhile, Bayern can advance if they beat struggling Villareal at the Allianz Arena.
Netherlands winger Arjen Robben marked his return from injury in Bayern's 1-0 loss to Borussia Dortmund on Saturday, although midfielder Bastian Schweinsteiger remains sidelined after breaking his collarbone against Napoli.
The loss to Dortmund cut Bayern's Bundesliga lead to two points.
"I think the team on Tuesday will be another proposition," Bayern coach Jupp Heynckes said.
With the Champions League final to be played in Munich next May, expectations are high for Bayern.
"We have the quality, but you need luck, too," Bayern chairman Karl-Heinz Rummenigge said. "Pressure can be counterproductive in football."
Villarreal are without their top scorer after Giuseppe Rossi had knee surgery earlier this month, although the Yellow Submarine beat Real Betis 1-0 on Saturday.