For 15 minutes or so the "farmers" were making hay at Estadio Jose Alvalade, granted plenty of open field to harvest by their well-heeled opponents.
As they did in their stunning 3-1 quarter-final victory over Manchester City, Lyon made a mockery of the derisory labels attached to Ligue 1 as they repeatedly scooted past Bayern Munich's high wire high line.
Pep Guardiola's uncharacteristic caution against Lyon has been rightly castigated, but how that game might have looked had City "just gone for it" was illustrated by an uncomfortable opening for Hansi Flick's in-form Bundesliga champions.
For all the enviable attacking gifts of Bayern's wide defenders Joshua Kimmich and Alphonso Davies, it was Lyon's more unheralded wing-backs Leo Dubois and Maxwel Cornet roving into space.
Cornet might have added to his quarter-final goal after Memphis Depay should have opened the scoring. Karl Toko Ekambi then hit the post. Were we really heading for an all-French final on Sunday? Were we ready to confront the imminent butter mountain of farmers' league gags?
Handily for Bayern, Serge Gnabry answered both those questions with an emphatic "no" 60 seconds after Ekambi tested the base of Manuel Neuer's left post.
Paris Saint-Germain will contest their maiden Champions League final on Sunday, when Bayern go for their sixth title in Europe's top competition. When it comes to the crunch moments, such historical weight feels like it can propel a side when it has no logical right to do so.
Gnabry made a particularly literal contribution to this phenomenon in the 18th minute in Lisbon by turning into Arjen Robben – cutting in from the right wing, opposition shirts in scattered pursuit, and rifling home with his trusty left boot, just like Bayern's hero of 2013 and European title number five.
For his next impression, the Bavarians' brilliant winger opted for a current team-mate as opposed to a former one. Robert Lewandowski inexplicably failed to add to his vast goal haul when he slid in at point-blank range to meet the ball with his backside. Gnabry was on hand to smuggle home and disprove the impression that Thomas Muller has a monopoly on such goals for Bayern.
If only Flick's back four were doing a similarly passable impersonation of a solid defence. When Lyon's weekend hero Moussa Dembele came on for Depay in the 58th minute he quickly wrought havoc – launching a move that concluded with Ekambi wilting under the whites of Neuer's eyes.
On Sunday, those chances will be falling to Angel Di Maria, Kylian Mbappe and Neymar – even if the latter's finishing in the Portuguese capital has been no cause for celebration up until this point.
Benjamin Pavard might return if passed match fit, allowing Kimmich to revert to a central midfield role and give a little more protection to the heart of defence, where Niklas Sule replaced Jerome Boateng at half-time and proved an at times plodding companion to David Alaba.
Lyon's great favour to their compatriots here was showing Bayern are far from infallible. On the other hand, the men from Munich have now won 20 in a row and are unbeaten in all competitions since December 7. The parade of talent following Sule from the bench – Kingsley Coman, Philippe Coutinho, Corentin Tolisso and Pavard – was frankly ludicrous.
Having seen Lewandowski head his 55th – that's fifty-fifth – goal of the season to crown a 3-0 win, Flick might just to let his flying machine soar and let PSG deal with it. Unleash Kimmich and Davies, let Leon Goretzka and Thiago purr from midfield and care not a jot what goes on behind them.
Had Lyon taken their early chances, we might have had a repeat of July's Coupe de la Ligue final, which finished 0-0 before PSG won on penalties.
It is impossible to see anything similar unfolding at Estadio da Luz on Sunday, with the cream of Europe's 2020 crop giving every indication we are in for a classic.