Chile striker Mauricio Pinilla boosted Sporting's hopes of playing in the UEFA Cup final in their own Alvalade stadium with a scorching winner in the semi-final first leg against AZ Alkmaar this evening.
The substitute unleashed a dipping shot from 30 metres that blazed past Henk Timmer 10 minutes from time to hand the Portuguese side a 2-1 win to take to the Netherlands next week.
The other tie between twice winners Parma and CSKA Moscow ended in a tepid goalless draw at the Tardini stadium.
Serie A strugglers Parma, as in previous rounds, fielded a virtual reserve side but CSKA were unable to take advantage in front of just over 7,000 fans.
Sporting, who have not won a European Trophy since the Cup Winners' Cup in 1964, needed a moment of sublime inspiration from substitute Pinilla to forge ahead against a resilient AZ.
The injury-hit Dutch side, beaten finalists in 1981, soaked up long periods of pressure but were always dangerous on the counter-attack.
Having never lost a European tie at their tiny Alkmaarderhout stadium AZ are still very much in the tie. AZ, who lined up with Robin Nelisse as a lone striker and packed the midfield, went ahead against the run of play on 36 minutes with their first chance, a right-wing cross from Kew Jaliens falling for Denny Landzaat to sweep a low first-time shot past Ricardo.
The lead lasted barely a minute, however, as Cameroonian Rodolph Douala took advantage of a lucky ricochet to lash home a fierce low shot past Timmer.
Parma coach Pietro Carmignani has made no secret that his side's priority is maintaining their Serie A place and he again rested key players against CSKA. Italy striker Alberto Gilardino and midfielder Domenico Morfeo were not even on the bench as Carmignani fielded four youth-team players.
Chances were few and far between, Parma's Fabio Vignaroli bringing the first save out of either keeper with a thundering 20-metre drive that CSKA's Igor Akinfeyev parried out eight minutes from time.