Manchester United are looking to complete the job over Club Brugge in their Champions League play-off second leg on Wednesday while Italy's Lazio may have slightly more to do to secure a place in the group stages.
The English Premier League giants have a two-goal lead to take to Belgium after a 3-1 win at Old Trafford last Tuesday, while Lazio have a slender 1-0 advantage for their second leg against Bayer Leverkusen in Germany.
A 2-0 win for Brugge at the Jan Breydelstadion would be enough to take them through at United's expense (on the away goals rule), but United -- three-time winners of the Champions League -- are confident after Marouane Fellaini's late third goal in the first leg.
"It (Fellaini's goal) makes a difference because 2-1 is a very difficult result," said United boss Louis Van Gaal after the victory last Tuesday.
Brugge boss Michel Preud'homme, on the other hand, was less optimistic after conceding the third goal in Manchester.
"This last goal was very bad for the confidence," said former Belgian international Preud'homme.
"It's a pity we let this one in," added the 56-year-old, who guided Brugge to the Belgian Cup last season.
Manchester United -- winners in 1968, 1999 and 2008 -- didn't feature in the competition last season but had previously reached the group stages for 18 years in succession.
Brugge, meanwhile, haven't made the group stages since the 2005/06 season when they finished third in Group A behind Juventus and Bayern Munich.
Lazio go to Bayer Leverkusen hoping to defend a one-goal advantage and reach the main draw for the first time since the 2007/08 season.
Keita Balde Diao's second-half winner at the Stadio Olimpico in Rome was the difference between the two sides last week, but Leverkusen are seasoned campaigners who have made the round of 16 in three of the last four seasons and were only edged out on penalties by 2014 runners-up Atletico Madrid at that stage last campaign.
Runners-up in 2002, Leverkusen have won two out of two domestically, while Lazio also got off to a winning start in Serie A on Saturday with a 2-1 home win over Bologna.
One player missing for the Bundesliga side is new Chilean signing Charles Aranguiz, who tore his Achilles tendon just one week after joining from Brazilian club Internacional.
"We've all been hit hard by the news and we're all suffering with him," said Leverkusen's sporting director Rudi Voeller.
"We will do everything we can so that Charles comes back as quickly as possible from this bad injury."
Elsewhere, Sporting Lisbon take a 2-1 lead to Russia against CSKA Moscow in the hope of securing a place in the main draw for the second successive season.
The Portuguese giants struck late on through Islam Slimani at the Jose Alvalade in Lisbon, but will be wary of a CSKA side who have six wins out of six in Russia this season.
The 2010 quarterfinalists were knocked out in the group stages last season but will fancy their chances of overturning the narrow deficit at the Arena Khimki.
Belarus champions BATE Borisov are favourites to reach the group stages for the fourth time in five years as they take a 1-0 advantage to Serbia for their second leg against Partizan Belgrade, who haven't qualified for the main draw for five years.
Astana are 90 minutes from making history as they look to become the first Kazakh team to qualify for the main competition.
They take a 1-0 lead to the Cypriot capital Nicosia for their second leg against 2012 quarterfinalists APOEL, who are no strangers to the group stage having qualified again last season.
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