Ronaldo's sensational return came as a shock towards the end of the transfer window, with United's neighbours Manchester City having appeared favourites to sign the Portugal captain.
The 36-year-old is in line for a second United debut on Saturday when Ole Gunnar Solskjaer's side face Newcastle United - the team Ronaldo netted his only Premier League hat-trick against during his first stint at the club.
And Pogba is relishing the prospect of potentially playing with the five-time Ballon d'Or winner, who became the leading goalscorer in men's international football when he netted a double in Portugal's 2-1 win over the Republic of Ireland last week.
"It's always a pleasure to play with the best, it’s a plus for the players to be able to train with a great player," Pogba said.
"He's going to raise the level of the team."
Ronaldo spent six years at Old Trafford between 2003 and 2009, scoring 118 times in 292 appearances as he collected three Premier League titles and a Champions League crown before joining Real Madrid.
It is not just in attack that United have improved, though, as Raphael Varane provides Solskjaer's defence with a World Cup-winning centre-back.
At 28, Varane is in the prime of his career. He joined from Madrid in July, with the move officially completed on August 14, making his debut in the 1-0 victory over Wolves, registering the assist for Mason Greenwood's winner.
During his time in Madrid, Varane won LaLiga three times and triumphed in the Champions League four times, while also winning the 2018 World Cup with France.
Pogba, too, was a part of the 2018 success in Russia, and he knows all about the qualities Varane brings to the table.
"Raph's [Raphael Varane] arrival is a positive for the club, we have a great relationship, we've known each other for a while," Pogba continued.
"I'm happy that he's with us at Manchester [United] to bring his experience and quality to the table."
Varane put in an accomplished performance in his United bow, making a team-high five clearances, successfully completing one tackle and winning four of the eight duels he competed for.