The home side are level on points with Belarus at the top of the table, while their visitors are yet to pick up a point.
Match preview
Having previously failed to challenge for a Euro 2024 playoff place, Bulgaria's recent renaissance continued in September, as they followed a gritty goalless draw in their opening Nations League fixture with a hard-fought victory in Northern Ireland.
After sharing the spoils with Belarus in a game played on neutral soil, the Lions travelled to Belfast, where Kiril Despodov's first-half strike was sufficient to secure maximum points and take them joint-top of the Group 3 standings.
Having inherited a squad low on confidence late last year, head coach Ilian Iliev is yet to lose as national team boss, with six draws and two wins from his eight matches in charge.
Last time around, Bulgaria finished second in their League C group, finishing seven points behind Georgia; this season, such a result would secure a playoff in UEFA's updated format - though first place will surely be their target.
Iliev's side would not only achieve automatic promotion by claiming top spot in November, but a potential back-door route to the 2026 World Cup would also await should they falter during qualification.
After emerging from the shadows over the past few years, Luxembourg have become one of Europe's most improved minnows - though they are still seeking a first-ever win over Saturday's hosts.
Following four straight defeats for the loss of 11 goals, Die Roten Lowen drew both of their last two meetings with Bulgaria, most recently playing out a goalless stalemate in 2022.
Like their Bulgarian counterparts, Luxembourg failed to qualify for Euro 2024, but they did reach the playoff semi-finals after accumulating a record 17 points from 10 group matches.
So far in the 2024-25 Nations League, a squad still overseen by long-serving coach Luc Holtz has failed to build on that progress, registering neither a point nor a goal last month, despite having much more of the ball than their first two opponents.
Having lost 2-0 in Northern Ireland, Luxembourg were then edged out by a late strike at home to Belarus, leaving them in distinct danger of relegation to League D.
Bulgaria Nations League form:
D
W
Bulgaria form (all competitions):
W
D
D
D
D
W
Luxembourg Nations League form:
L
L
Luxembourg form (all competitions):
L
W
L
L
L
L
Team News
Luxembourg coach Luc Holtz caused some surprise when announcing his 25-man squad, as Gerson Rodrigues - currently playing in China's second division - was recalled following a disciplinary issue last month.
Furthermore, Alessio Curci, Chris Philipps, Marvin Martins and Seid Korac all return, while Michael Omosanya is selected for the first time since 2022.
Vincent Thill and Yvandro Borges are sidelined by injury, Olivier Thill and Lars Gerson were both dropped; Christopher Martins should feature in Tuesday's game against Belarus but is ruled out of meeting Bulgaria by suspension.
Meanwhile, the hosts have Filip Krastev back from a ban after the PEC Zwolle playmaker was sent off in their opening Nations League contest; however, Leeds United midfielder Ilia Gruev recently suffered a serious knee injury.
Having been handed his debut last month, Fabian Nurnberger is set to continue at left-back: the Germany-born Darmstadt defender qualified for selection through his Bulgarian mother.
Up front, captain and leading active scorer Kiril Despodov should support centre-forward Aleksandar Kolev, though the latter has yet to get off the mark in senior international football after eight caps without a goal.
Bulgaria possible starting lineup:
Mitov; Popov, Petkov, Atanasov, Nurnberger; Kostadinov, Chochev; Despodov, Krastev, Kirilov; Kolev
Luxembourg possible starting lineup:
Moris; Dzogovic, Mahmutovic, Carlson, Jans; Barreiro; Sinani, Olesen, S. Thill, Bohnert; Rodrigues
We say: Bulgaria 1-0 Luxembourg
Bulgaria could keep their positive run going this weekend, as Luxembourg tend to boss possession without fully punishing their opponents.