For the second year running, PSG's star signing Neymar will be unavailable for the return leg. Last season the Brazilian was injured just after the first leg against Real Madrid.
The Spaniards disposed of PSG and ultimately claimed the European Cup for a third consecutive season to take their overall tally up to 13.
PSG are hankering after their first triumph in European club football's most prestigious competition and Neymar was drafted in for 222 million euros from Barcelona in July 2017 to help deliver the prize.
The 27-year-old will be an onlooker this season for both legs after suffering an injury to the same bone that kept him on the sidelines between February and May 2018.
To see the world's most expensive footballer demobilised in a - by comparison - mundane Coupe de France game against Strasbourg was not part of PSG's domination plan.
"It's not the time to beat ourselves up or to lose confidence," said PSG boss Thomas Tuchel on the eve of the meeting with Bordeaux.
"Yes, we have to stay on our toes and we also have to look for improvements. But it is not the moment to doubt ourselves. We have to remain calm."
Only a titanic meltdown should stop PSG from winning a sixth French title in seven years. They are 10 points clear of second placed Lille who have played two games more than the pacesetters.
Éric Bedouet's Bordeaux are inconsistent and lie in 12th. Bordeaux ought to be dispatched with a minimum of fuss.
But, of late, PSG have toiled while performing the simplest of tasks.
On 6 February, the multi-million euro squad needed extra-time to see off the third division outfit Villefranche Beaujolais in the last 16 of the Coupe de France.
Even though the match finished 3-0 to the holders, it was underwhelming. And it came three days after PSG suffered their first league defeat of the season at Lyon.
"I have to protect the players who have played a lot recently," said Tuchel. "We have to get the right mix between doing what's best for the squad and what's best for the players."
The Champions League last 16 draw pitting PSG against Manchester United appeared propitious for the French outfit. PSG were racing away with the French title and United were already also-rans in England's Premier League.
United coach Jose Mourinho was at loggerheads with his star-studded squad and, worse for the United faithful reared on the rip-roaring brio of Alex Ferguson's sides, the football was sepulchral.
But that was so October 2018. Mourinho has been dismissed and replaced by Ole Gunnar Solskjaer who has injected pace and panache as well as Premier League points. The former United striker has won nine and drawn one of his 10 games in charge.
Mission: Manchester appears less possible. Yet PSG can harbour hope.
Marco Verratti has returned after three weeks from an injury to his left ankle and could slot back into his sentinel role in front of the defence. Marquinhos, Julian Draxler and Dani Alves have looked cumbersome in the post in his absence.
"We'll see if Marco can play against Bordeaux," said Tuchel. "If he can he'll start the match."
If Verratti emerges unscathed from the Bordeaux match, he will be in the mix for game at United.
Even without Neymar, PSG can boast a 330 million euro attacking troika of Kylian Mbappé, Edinson Cavani and Angel di Maria.
The would-be king may be lame but a battle royal awaits.