Dudelange stun double winners Salzburg
HJK Helsinki thumped seven goals past hapless visitors KR Reykjavik, with Juho Makela scoring a hat-trick, and Alexander Frei scored twice to give Swiss champions FC Basel a 2-0 win at Flora Tallinn in other second round, first leg qualifiers.
Salzburg have never reached the Champions League group stage since the club was taken over by Red Bull in 2005 despite the energy drinks company pouring money into the club and their latest attempt got off to a miserable start.
Aurelien Joachim scored the only goal with a rasping 25-metre effort 15 minutes from the end, his fifth goal of the competition, while Salzburg had substitute Jonathan Soriano sent off for a second bookable offence in the last minute.
Makela opened the floodgates for HJK with a 13th minute goal and they led 2-0 at halftime thanks to a Mika Vayrynen penalty.
Two further goals from Makela, two more from Joel Pohjanpalo and one from Rasmus Schuller completed the rout after the break.
Basel, forced into the qualifying rounds after the Swiss league dropped down UEFA's complex rankings system, had to wait for the last half hour before securing their win in Estonia.
Frei, Switzerland's all-time leading scorer, converted a David Degen cross just after the hour and slotted home a penalty three minutes from time.
Moldovan champions Sheriff Tiraspol, beaten in the playoff stages in the last two seasons, won 1-0 at Armenia's FC Ulisses thanks to a Serghei Gheorghiev goal in Yerevan.
Serbian champions Partizan Belgrade thumped FC Valletta 4-1 away while Czech side Liberec won 1-0 at home to Ukraine's Shakhtar Donetsk thanks to Vojtech Hadascok's first-half strike.