Hooker Archie Vanes scored a hat-trick of tries in his first Champions Cup start as Leicester claimed a dramatic win over Stade Francais.
Jamie Shillcock's 52-metre penalty gave the Tigers a narrow lead with 14 minutes left.
Stade Francais were held up over the line late in the game as Leicester defended resolutely.
The Tigers ended the game with 14 men after full-back Mike Brown was sin-binned for a deliberate knock-on.
Vanes had grabbed the first of his three tries in the seventh minute, the 22-year-old also crossing just before half-time and after the break in an impressive display.
But the French Top 14 side hit back with converted tries from Mathieu Hirigoyen, Charles Laloi and Leo Barre.
The Pool 4 tie was level at 24-24 when Shillcock nervelessly slotted his second penalty from long range, sparking an intense finale which saw Leicester pushed back into their own 22.
Substitute Harry Wells got underneath Stade Francais' drive over the line and then won a turnover in the 86th minute as the Tigers clinched a second consecutive Champions Cup win.
Much-changed Tigers dig deep
The Tigers made 13 changes from the side that opened the European campaign with victory over the Stormers.
After Vanes' opening effort off the back of a line-out they were quickly pegged back by Hirigoyen's try converted by Joris Segonds.
Leicester were also a man down for a quarter of the first half when Charlie Atkinson was sent to the sin-bin for a high tackle, but they kept Stade Francais at bay and were 14-10 ahead at half-time when Vanes claimed his second try.
Laloi plundered a try down the blindside to put the hosts ahead again a minute into the second half, but when Vanes plunged over to seal his hat-trick and Shillcock converted, Leicester were back in front.
Shillcock's penalty left Stade Francais needing a converted try to draw level and they did so through Barre's long run to the line following a brilliant reverse pass from Jules Gimbert, and Segonds' conversion.
Pinned back on their own line in the closing stages, Wells' crucial contribution sealed a success that put Leicester second in Pool 4 behind leaders Leinster, with a trip to defending champions La Rochelle next on 14 January.
Line-ups
Stade Francais: Barre; Hamdaoui, Marchant, Jeremy Ward, Laloi, Segonds, Zabalza; Castets, Ivaldi, Alo-Emile, Gabrillagues, Pesenti, Macalou, Briatte, Hirigoyen.
Replacements: Peyresblanques, Alo-Emile, Kodela, Azagoh, Ahmed, Gimbert, Chapuis, Van der Mescht.
Leicester Tigers: Brown; Watson, Kelly, Kata, Hassell-Collins; Shillcock, Whiteley; Cronin, Vanes, Heyes, Martin, Carter, Liebenberg, Rogerson, Hatherell.
Replacements: Theobald-Thomas, Whitcombe, Hurd, Wells, Ilione, Powell, Atkinson, Simmons.
Referee: Nika Amashukeli
