The 36-year-old joined the American outfit in the summer on a free transfer following the expiration of his contract at Paris Saint-Germain.
And he spearheaded the club to their first major honour as he helped them win the Leagues Cup - chipping in with ten goals and one assist from seven outings.
But he wasn't even named in the top three of the 2023 MLS season, though that it is down to the fact that he arrived midway through.
Injuries limited him to just six appearances in the Eastern Conference, where he scored just once and provided two assists.
It was a hugely disappointing MLS campaign for Inter, who failed to qualify for the playoffs and finished 27th out of all 29 teams.
As a result, Messi's Argentine compatriot Luciano Acosta has scooped the Landon Donovan MLS MVP award.
The 29-year-old has enjoyed a stunning term for FC Cincinatti, where he found the back of the net 17 times in the regular season, while scoring once in the playoffs.
That is in addition to ten assists with a further two in the post-season championship to help Pat Noonan's side win the Supporters' Shield.
He proved to be a popular choice, as he claimed 60.37 per cent of the vote in a landslide win, with Los Angeles FC's Denis Bouanga [14.97 per cent] and Atlanta's Thiago Almada [ 6.46 per cent] rounding up the top three.
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Commenting on his success, he said: "I'm very proud of this team. I think everybody deserves something this year. We deserve more. We have to give it our all. Let's go."
Acosta then joked: "I don't want to go to practice. I won the MVP!"
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The former Boca Juniors star, who has never been capped by Argentina, will be hoping to finish an incredible year by winning the MLS Cup, with Cincinnati one match away from the final.
They first have to get past Colombus Crew in Saturday night's Eastern Conference final where they would then set up a clash against either LAFC or Houston Dynamo.