The two league phase hopefuls played out a 1-1 stalemate on Czech soil last week, where this week's visitors to Romania were forced to do it the hard way.
Match preview
Earning their Champions League stars with an 11-1 aggregate annihilation of Virtus and a slender 2-1 win over Maccabi Tel Aviv over two legs, FCSB were on course for a precious advantage on Czech soil last week, where Joyskim Dawa headed in the opening goal just past the hour mark.
The Romanian champions' lead lasted for all of 18 minutes, though, as Sparta Prague substitute Victor Olatunji ensured that Tuesday's visitors would avoid a gut-wrenching defeat on home turf, although Ilias Charalampous's men would certainly have left with more of a spring in their step.
One-time European champions in the 1985-86 edition - when they were formerly known as Steaua Bucharest - FCSB's continental record has been far more modest in recent seasons, underscored by their failure to reach the Champions League proper since 2013-14.
The 27-time Romanian champions have also endured several short-lived runs in the Europa League, as well as a group-stage exit in the 2022-23 Europa Conference League, and the defence of their top-flight crown also got off to an unpleasant start.
However, Charalampous's troops made it fourth time lucky in Liga I action on Friday, twice coming from behind to defeat Farul Constanta 3-2 and pick up their first top-flight win of the campaign, although they required a 94th-minute Darius Olaru penalty to get over the line.
Sparta Prague's 2024 in Europe will perhaps be best remembered for their 11-2 embarrassment at the hands of Liverpool in last season's Europa League last 16, but a first Champions League proper appearance since 2005-06 is firmly within their sights.
On account of pipping great rivals Slavia Prague to the 2023-24 Czech First League title, Lars Friis's men entered Champions League qualifying at the second hurdle and did not break much of a sweat in their opening tie with Shamrock Rovers, hitting them for six over two legs.
Those two successes formed part of a five-match winning sequence for the Czech titans, whose victorious streak came to an end in last week's opening affair with FCSB, but they reverted to type at the weekend with a 2-1 league success over Bohemians 1905.
Boasting 12 points from an available 12 in top-flight action so far, Sparta have already built up a slender lead over Slavia at the top of the Czech First League rankings and are now unbeaten in a staggering 20 competitive matches since that 6-1 Anfield humiliation back in March.
Swedish giants Malmo or Greek powerhouses PAOK will be waiting for the victor of Tuesday's match in the final round of Champions League qualifying, while the losers will be condemned to a Europa League playoff against LASK Linz of Austria.
FCSB Champions League form:
FCSB form (all competitions):
Sparta Prague Champions League form:
Sparta Prague form (all competitions):
Team News
No fewer than seven FCSB players were cautioned in the first-leg draw with Sparta Prague, including goalscorer Dawa, who has now been booked in three straight qualifying games and must therefore serve a suspension on Tuesday night.
One-time Tottenham Hotspur man Vlad Chiriches will likely deputise for Dawa in the Romanians' backline, while attacker William Baeten was taken off just 16 minutes after his half-time introduction in the first leg and will seemingly miss out too.
Fellow attacker Alexandru Musi also picked up an injury in Friday's success, joining Baetan, Alexandru Pantea (ligament) and Octavian Popescu (foot) in the hosts' medical bay and leaving Charalampous slightly short of wide options.
In contrast, Sparta Prague managed to keep their heads in the first leg - only having two players booked - although Friis had to substitute left-back Imanol Garcia de Albeniz just 23 minutes into the win over Bohemians due to injury.
Albeniz is now one of four stricken Sparta defenders in the care of the doctors, the others being Asger Sorensen, Martin Suchomel and captain Filip Panak, while teenage winger Roman Mokrovics is also out of contention with an unspecified issue.
With Albeniz in the treatment room, Matej Rynes will come straight back into Friis's 3-4-3 system as the visitors' left-wing back, and there should also be a recall for Slovakia international Lukas Haraslin, one of his nation's stars of Euro 2024.
FCSB possible starting lineup:
Tarnovanu; Cretu, Chiriches, Ngezana, Radunovic; Sut, Lixandru; Stefanescu, Olaru, Phelipe; Popa
Sparta Prague possible starting lineup:
Vindahl; Vitik, Zeleny, Ross; Preciado, Kairinen, Sadilek, Rynes; Birmancevic, Kuchta, Haraslin
We say: FCSB 0-2 Sparta Prague (Sparta Prague win 3-1 on aggregate)
FCSB's first-leg showing demonstrated that the Romanians can be a tough nut to crack, but with Dawa banned and fresh injury concerns in attack, the hosts will struggle to replicate their first-leg display.