The world's most expensive player was handed a two-match suspension after his involvement in an unseemly brawl at the end of PSG's 1-0 home defeat by Marseille recently.
Without him, his teammates bounced back from losing their opening two games of the season and recorded successive victories against Metz (1-0) and Nice (3-0).
"We are suffering a lot and we are really tired," said coach Thomas Tuchel after that latter outing, and Neymar's return can only improve their prospects of keeping that winning run going when they visit a Reims side who are winless in Ligue 1 and were in Hungary on Europa League duty on Thursday.
Yet while PSG have now recovered the raft of players -- including Neymar and Kylian Mbappe -- who tested positive for Covid-19 following a holiday after their run to the Champions League final, the problems are not going away for Tuchel.
Neymar faces further disciplinary action having been accused by Marseille of racially abusing their Japanese defender Hiroki Sakai in that same recent encounter.
The French league will investigate those claims, and claims Neymar used a homophobic slur against Marseille's Alvaro Gonzalez, who the Brazilian says directed a racial slur at him. A decision in that case is expected next week.
In the meantime, PSG learned on Wednesday that Angel Di Maria must serve a four-match ban for spitting at Gonzalez.
The Argentine can feature this weekend but will not then be able to play another Ligue 1 game until early November, by which time PSG's Champions League campaign will be well underway.
While Paris have been linked with a move for Chelsea midfielder Tiemoue Bakayoko, Tuchel has lost left-back Juan Bernat to a serious knee injury and concerns remain about the form of Mauro Icardi.
The Argentine striker did enough on loan last season from Inter Milan for PSG to sign him permanently for an initial reported fee of 50 million euros.
However, he played no part in the Champions League semi-final win over RB Leipzig or the final against Bayern Munich, missed PSG's first two league games this season due to a positive Covid-19 test, and has failed to find the net in the two outings since his return.
At least Mbappe looked lively last weekend against Nice, winning and converting a penalty before making another goal for Di Maria.
One to watch: Jonathan David
It has been a slow start to life in France for David, who was one of the biggest signings made by a Ligue 1 club in the summer as Lille paid a reported 27 million euros ($31.4m) to recruit the 20-year-old Canada striker from Belgian side Gent.
Brought in to replace Victor Osimhen, who was sold to Napoli, David has big boots to fill. Like Osimhen before him, David was prolific in Belgium but has struggled in his first four games in Ligue 1. Can he get his first goal this weekend?
Key stats
26 - PSG have used 26 different players in four league games this season.
4 - The number of matches PSG's Angel Di Maria will miss -- after this weekend -- due to suspension.
21.5 - The average age of early league leaders' Saint-Etienne's starting line-up last weekend, with veteran coach Claude Puel having rejuvenated his squad. It is further evidence of Ligue 1's ability to keep producing young talent.
Fixtures (kick-offs GMT)
Friday
Lille v Nantes (1900)
Saturday
Saint-Etienne v Rennes (1500), Marseille v Metz (1900)
Sunday
Bordeaux v Nice (1100), Angers v Brest, Dijon v Montpellier, Monaco v Strasbourg, Nimes v Lens (all 1300), Lorient v Lyon (1500), Reims v Paris Saint-Germain (1900)
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