On Friday, Brazil head coach Dorival Junior announced his selection for the 2024 Copa America, but there was no room for Richarlison, who has struck 20 goals in 48 appearances for his nation.
The former Everton and Watford man has failed to replicate his form from the winter months after a couple of knee injuries, but he is now fit and firing again, scoring one and setting up another in last weekend's 4-2 loss to Liverpool.
Richarlison's omission from the Brazil ranks therefore came as a surprise initially, although Dorival Junior revealed that the attacker had picked up a calf issue, which would render him unavailable for the tournament.
There was no communication from Tottenham regarding an injury to Richarlison, but the South American was indeed absent from the matchday squad for Saturday's Premier League clash with Burnley in North London.
Postecoglou "assumed" Richarlison issue was minor
Instead, Dejan Kulusevski, James Maddison and Brennan Johnson supported Son Heung-min in the number nine role, as Spurs triumphed 2-1 to send Burnley back down to the Championship.
Speaking to the press after the victory, as quoted by football.london, Postecoglou revealed that Richarlison had sustained his issue in Friday's training session, although he did not anticipate at the time that it would become anything serious.
"It was unfortunate. I know I did the press conference yesterday, but it was literally the last kick of the game and I saw him hobble off and I assumed it was nothing serious," Postecoglou said.
"Then it didn't get any better later on in the evening and he was sent for a scan on his calf and I still don't know the results of that to be honest, but watching him today he was still hobbling about."
With Richarlison watching on helplessly from the sidelines, Spurs fell behind early doors to a shock Jacob Bruun Larsen effort, but the hosts mustered up a response before the break as Pedro Porro's rocket found the roof of the net.
Postecoglou "couldn't be happier" for goalscoring defender
A second half of huffing and puffing finally paid dividends with eight minutes of normal time left to play, as Spurs' Player of the Year Micky van de Ven curled a low strike into the bottom corner to relegate Burnley and keep Tottenham's fleeting top-four hopes alive.
Postecoglou was especially made up for fans' favourite Van de Ven, whose influence has not waned since his serious hamstring injury, adding: "Micky's been through a lot with injury, and even then he's bounced back so well from that to maintain an elite level of performance so I couldn't be happier for him.
"There are a lot of these players - it's Micky's first year in the Premier League, [Guglielmo] Vicario's, Destiny's [Udogie]. Pape's first full season. There's so much growth in us and what we've been through this year both good and bad is great for us."
By snapping their four-game losing sequence, Tottenham have cut the gap to fourth-placed Aston Villa down to four points, although the Lions will nab the final Champions League spot by beating Liverpool on Monday.
Should Unai Emery's side fail in that mission, though, Tottenham could still catch their West Midlands foes with satisfactory results against Manchester City and final-day opponents Sheffield United.