Two-time winners Tottenham Hotspur carry a narrow advantage into their Europa League playoff second leg against AEL Limassol of Cyprus while their domestic rivals Hull need to overturn a 1-0 deficit to keep alive their first ever European campaign.
Thirty one places are up for grabs in the final qualifiers to reach the group phase draw on Friday in Monaco and governing body UEFA have thrown a valuable carrot in front of the potential winners.
The triumphant side in the May 25, 2015 final at Warsaw will, for the first time, automatically qualify for next season's Champions League.
Spurs, who are off to an unbeaten start to their campaign with a 2-1 win over Limassol and back-to-back wins in the Premier League are enjoying life under new manager Mauricio Pochettino, who has got the North Londoners smoothly out of the gate.
The team are looking for their first silverware, since Spaniard Juande Ramos guided them to the 2008 League Cup, although their last European success dates back to 1984 when they won their second UEFA Cup, now the Europa League, in a penalty shootout against Anderlecht.
"The Europa League is now a different competition," said Pochettino.
"If you won it last year you basically got nothing, just a trophy but now the Europa League gives you the opportunity to play in the Champions League. That is a big challenge for us," added the 42-year-old Argentine.
Hull qualified for their first ever European competition as FA Cup runners-up last season, at the hands of Arsenal, but manager Steve Bruce must mastermind a comeback from 1-0 down against Belgian Cup winners Lokeren.
Elsewhere, Belarusian outsiders Dinamo Minsk stand on the brink of their first qualification for the group stages of a European competition after a run of five consecutive clean sheets including a 2-0 first leg win over Portugal's Nacional last week.
Their water-tight defence, built around stalwart Sergei Politevech, has only leaked eight goals in 21 league matches.
"It is very important to avoid goals and we always prioritise getting a result and play accordingly," said the 24-year-old Belarus international defender.
"Our defensive performances are of utmost importance as we want to achieve our aims."
France risk losing two clubs before the draw with bitter local rivals Lyon and Saint-Etienne both needing second leg victories.
Hubert Fournier's seven-time champions Lyon gave up two late goals at home to Romania's Astra Giurgiu as they were beaten 2-1 while Saint-Etienne slumped to a 1-0 defeat against Karabukspor in Turkey.
PSV Eindhoven, the 1978 UEFA Cup champions, take a 1-0 lead to Belarus where they tackle Shakhtyor Soligorsk while Dutch rivals Feyenoord have an away goal to protect after coming back to force a 1-1 draw against Zorya Luhansk of Ukraine.
Spanish sides are well positioned to reach the next round after Villarreal thrashed Astana of Kazakhstan 3-0 and Real Sociedad edged Russian outfit Krasnodar 1-0 thanks to a 71st minute winner from Xabi Prieto.
Italian interests rest with Torino, as they drew 0-0 on the road at RNK Split of Croatia, while Inter Milan are in the driving seat after overpowering Stjarnan 3-0 in Iceland.