Having spent nine years locking horns with an eternal rival in La Liga, an iconic figure at Camp Nou now finds himself freed of a long-running duel in the Spanish top-flight.
With Ronaldo having made a €112 million (£101m/$130m) move to Serie A, the path has been cleared for a five-time Ballon d’Or winner to monopolise a domestic stage.
Messi believes Barcelona can take advantage of that, with Clasico foes Real not the force they once were, but is also aware that a quest for European glory could be disrupted by heavyweights in Turin.
The Argentine forward told Catalunya Radio: “Real Madrid are one of the best teams in the world and they have a great squad [but] it's evident that the absence of Ronaldo makes them less good and makes Juventus [one of the] clear favourites to win the Champions League.”
Messi added on Ronaldo’s shock departure from the Santiago Bernabeu: “It surprised me [when he left].
“I didn't imagine him leaving Madrid or joining Juventus. There were a lot of teams that wanted him. It surprised me, but he has gone to a very good team.”
While stunned to see Ronaldo head for pastures new, Messi is delighted to have seen fresh faces arrive at Barcelona.
Arthur, Clement Lenglet, Malcom and Arturo Vidal have joined the ranks at Camp Nou and are considered to have raised the collective quality.
Messi said: “I didn't know much about Arthur before [he joined], but he's really similar to Xavi.
“He's really safe and reliable [on the ball]. He has the style of a player that's come through La Masia. He plays well over short distances, he doesn't lose the ball... He's got to grips really quickly with the team's dynamic.”
Barca’s new-look squad have made a flying start to the 2018-19 campaign, with an 8-2 mauling of SD Huesca in their latest outing allowing them to sit proudly at the top of the Liga standings.
Real have also collected maximum points from their three games to date, with the Blancos hoping to prove that they can sustain a challenge for the crown despite bidding farewell to Ronaldo.