FC Flora 1-1 FC Sheriff (Agg: 1-2) Moldovans hang on against determined Estonians and secure progress.
The Estonian champions trailed 1-0 from the first leg, but on home soil they were determined to reverse that result and Vjatseslav Zahovaiko fired in an early warning shot on eight minutes which went narrowly wide of the target.
Sheriff signalled their own intent in the 22nd minute when Cristian Tudor forced a fine save from Martin Kaalma. Soon afterwards Tor Hamre shot on target from close range for Flora only for Chidi Odiah to clear off the line.
Zahovaiko then broke through again only to be denied by the impressive Sebastian Hutan's one-handed save. Just before half-time, Sheriff gave a sign of things to come when Ion Testemitanu's deflected shot hit the post.
Flora press forward
Sheriff then began the second half strongly, dominating possession. Only in the last quarter-hour did Flora start to press forward again, with Ragnar Klavan missing an empty goal and Zahovaiko shooting wide seconds later.
With nine minutes to go Sheriff made Flora pay for their misses as Andriy Nesteruk won the ball on the edge of the area and sent a strong shot under the crossbar into the net.
Kristen Viikmäe gave Flora a lifeline by scoring their first goal of the tie, but there was no time for the two further strikes his side needed so it will be the visitors who meet Ukraine's FC Shakhtar Donetsk in the next round with the first leg in Tiraspol next Wednesday.
'Second half was better'
Following the triumph, Sheriff head coach Igor Nakonechnyi said: "We had serious difficulties in the first half, the second half was better and we were able to achieve the result we needed."
'We deserved to win'
Flora coach Arno Pijpers admitted: "We deserved to win this game, we managed to create good chances but the finishing was far from good. Our strikers do not have enough international experience to finish at such a level."