UEFA Champions League: Austria Vienna v Porto
Although the Austrian champions have no previous experience in the competition in its current format, Vienna were European Cup semi-finalists as far back as 1979, while they have regularly appeared in the Europa League and its predecessor the UEFA Cup, in which they were defeated in the second round by Jose Mourinho's Porto in 2002-03.
Nenad Bjelica's side have progressed through two rounds of qualifying before reaching the group phase, beating FH Hafnarfjordur of Iceland before squeezing past Dinamo Zagreb 4-3 on aggregate after Roman Kienast netted the all-important goal in the 82nd minute of the second leg.
Vienna clinched the Austrian Bundesliga title last season for the first time since 2005-06 by five points from Red Bull Salzburg, but are currently fifth eight matches into the current campaign and head into the Porto game off the back of two defeats and a draw in all competitions.
Porto, in comparison, have won all four of their league games and are currently top of the Primeira Lig.
The trip to Ernst-Happel-Stadion sees Paulo Fonseca's Porto return to the scene of the club's first European Cup success as they beat Bayern Munich 2-1 in what was then the Praterstadion in 1987.
Under new coach Fonseca, Porto are set for their 18th Champions League campaign, equalling Barcelona and Real Madrid and bettered only by Manchester United, who have appeared in 19, but they saw key players leave during the close-season.
Joao Moutinho and James Rodriguez both departed for Ligue 1 as they joined Monaco for a reported combined total of €70 million, although the acquisitions of Hector Herrera, Diego Reyes and – most notably – Juan Quintero have ensured the Portuguese champions remain an intriguing prospect.
Ahead of the start of their European campaign, Fonseca was relieved to pick up three points against Gil Vicente in a 2-0 win at the weekend before looking forward to Wednesday.
He said: "Winning was the goal. The goal is always to win and achieved that once again in a week that will be difficult.
"We have the first round of the Champions League and it was important to win against a confident opponent."
Joining Porto and Vienna in Group G are Zenit St Petersburg and Atletico Madrid.