They convene at Yokohama's Nissan Stadium, five years after the Selecao finally won Olympic gold for the first time by beating the Germans on penalties, in a redemptive finale at the Maracana.
One of the major football nations which takes the quest for podium places suitably seriously, Brazil have qualified for seven of the last nine Olympic Games; claiming two bronzes, three silvers and - at last - gold in Rio.
In fact, only once since 1976 have they failed to win a medal at all, but at the South American Under-23 Championships which serves as the continent's qualifying process, the Selecao were just 90 minutes away from failing to book their trip to Japan.
Already confirmed as tournament winners, arch-rivals Argentina needed only to avoid defeat in the pair's final-round fixture and had the incentive of potentially eliminating the reigning champions. Fortunately for Brazil fans worldwide, Hertha Berlin's Matheus Cunha netted twice as they ultimately ran out 3-0 winners.
While Cunha - then at RB Leipzig - finished the tournament as top scorer, fellow Bundesliga boy Paulinho also emerged as one of the team's most potent attacking weapons. This summer, the duo will be involved again, as head coach Andre Jardine seeks to lead his team out of a group also featuring outsiders Ivory Coast and Saudia Arabia, into the quarter-finals and beyond.
A friendly versus the UAE on Thursday night saw Arsenal's Gabriel Martinelli spring off the bench to help reverse a 2-1 deficit with just 12 minutes left to play. Within a minute of his arrival, he delivered a cross for Real Madrid starlet Reinier to volley in the equaliser. Shortly after, Martinelli notched a goal of his own - heading home the winner from close range.
Just one member of a squad featuring plenty of depth, he joins other young Europe-based players including Aston Villa's Douglas Luiz and Bruno Guimaraes of Lyon in midfield, plus Richarlison, Antony and Cunha up front. In addition, overage picks Dani Alves, Diego Carlos and goalkeeper Santos add a wealth of quality and experience which will surely trouble the Germans on Thursday.
Having been pipped at the post in Rio, the jury is out on whether Germany can go one better this time around, and despite their dominance of European football during much of the last century, their Olympic record remains rather modest.
Famously, East Germany claimed the gold medal in 1976, while the West managed to secure bronze 12 years later in Seoul, but the most recent Games was the first time for 60 years that a united German side actually competed.
Now current coach Stefan Kuntz, under whom Germany have reached three successive Euro Under-21 Finals - lifting the trophy in 2017 and again earlier this summer - will look to build on their achievement five years ago by guiding a squad featuring plenty of Bundesliga experience to at least the final four.
German top-flight regulars Nadiem Amiri, Maximilian Arnold and Max Kruse will be Euro '96-winner Kuntz's three over-age players, while RB Leipzig full-back Benjamin Henrichs and Hertha Berlin's Arne Maier are among the squad's more youthful talents.
Another Hertha player, Jordan Torunarigha, suffered alleged racist abuse towards the end of Saturday's warm-up friendly with Honduras in Wakayama, causing his teammates to walk off in solidarity. That controversial clash with the Central Americans was the Germans' only pre-Games fixture, so they may enter the competition against one of the favourites already on the back foot.
The embodiment of commitment to the national cause, Brazil forward Richarlison heads to Japan after taking part in the Copa America final defeat to Argentina earlier this month and featuring throughout the Selecao's ultimately unsuccessful campaign. The 24-year-old has already scored 10 goals in 32 appearances at senior level and is expected to lead the line on Thursday.
Though he has popped up in a creative midfield role and on the right wing at times since his return to the Campeonato Brasileiro, former Barcelona veteran Dani Alves is expected to revert to right-back for the tournament, while RB Bragantino's Claudinho is tasked with running the game centrally.
Head coach Andre Jardine generally opts for a 4-3-3 formation, with any two from Paulinho, Antony and Matheus Cunha asked to cut in and combine with Richarlison from the flanks.
As one of Germany's senior players, Union Berlin striker Max Kruse is hoping to carry his form from an outstanding season - during which he netted 11 times in the Bundesliga - into this competition.
Attacking midfielder Nadiem Amiri will take up the creative burden in behind the 33-year-old, while coach Stefan Kuntz - who also prefers a 4-3-3 - is expected to rely on young Arne Maier to carry over his Under-21 performances into yet another month of this action-packed year.
Brazil Under-23s possible starting lineup:
Santos; Alves, Carlos, Nino, Arana; Luiz, Guimaraes, Claudinho; Paulinho, Richarlison, Cunha
Germany Under-23s possible starting lineup:
Muller; Henrichs, Pieper, Uduokhai, Raum; Stach, Arnold, Maier; Richter, Kruse, Amiri
We say: Brazil Under-23s 2-0 Germany Under-23s
Recent international tournaments have taught us that greater individual quality does not always trump collective spirit and in-game cohesion, but Brazil's Olympic Selecao certainly has the edge when it comes to talent.
They can, therefore, get their quest for back-to-back golds underway with a win in Yokohama - the city where the senior side lifted the 2002 World Cup with a final victory against Germany.