Suarez will be allowed to train with the club and be unveiled, contradicting the punishments which seemed draconian and unnecessary when it was announced he would be banned from "all football activity."
The striker can now link up with his colleagues at the Ciutat Esportiva and show Luis Enrique exactly how he can fit into the club's tactical plans.
Suarez is also eligible to play in friendlies for club and country, so he could even make his debut on Monday in the Joan Gamper Trophy exhibition match at the Camp Nou.
The CAS said in a statement, per the Daily Mail: "The four-month suspension will apply to official matches only and no longer to other football-related activities (such as training, promotional activities and administrative matters)."
On July 1, Suarez was issued with his huge ban for biting Giorgio Chiellini during Uruguay's game against Italy in the World Cup.
Like the other two times he has bitten a player, in the cases of Otman Bakkal and Branislav Ivanovic, he avoided a red card but was retrospectively punished.
He clearly needs help with managing his temper and behaviour on the pitch, and this four-month layoff should provide adequate time for him to see a psychologist or similar.
However, there was no need to prevent him from being presented after he signed for Barcelona and no precedent to suggest that he should have been excluded from training.
Lawyer Daniel Cravo believed that FIFA were just trying to make a point with their severe ban. He told Sport:
I think FIFA wanted to show they could take action. There was a dissatisfaction with how other incidents had been treated in the World Cup and Suarez paid for them. Not even the sanction of [Zinedine] Zidane in 2006 or those of Leonardo and [Mauro] Tassotti in 1994 were as severe. Is the Suarez incident the worst in the history of the World Cup?
Suarez is still banned until October 26 and will miss eight matches with Uruguay, too.
The next question is over whether he will participate in El Clasico, which will take place on the weekend his ban ends.
Who would bet against him making a dream debut against Real Madrid, coming on as a late substitute in the Bernabeu to score the winner?
The man thrives on controversy, and making an impact like that would be right up his alley.
And, thanks to the ban on training being relaxed, it's more than feasible he will be in the squad for that match.
In a league in which even the smallest margins at the top can make a big difference, Barcelona will be glad that Suarez will be up to speed and synchronized with his Barca team-mates.
Like last season with Liverpool, when he was banned for the first few games, he may be able to hit the ground running when he hears the starter gun.