The 34-year-old Argentine spent more than two decades with the Spanish giants before leaving as a free agent in July.
“Lionel Messi is a player with huge intelligence and the ability to adapt at the highest level,” said Pochettino on the eve of the Champions League tie against RB Leipzig at the Parc des Princes.
“I and the rest of the staff are very pleased with him and he is happy to be here in Paris.
“I'm sure things will flow naturally and he will perform in the way that we expect and that he expects.”
Messi scored his first goal in his new colours in the 2-0 victory over Manchester City on 28 September in the Champions League.
On Tuesday night, Messi is expected to play in attack alongside Kylian Mbappé, Mauro Icardi and Angel Di Maria.
The Italy international Marco Verratti is likely to pull the strings from midfield as PSG aim to consolidate their supremacy in Group A.
The Ligue 1 pacesetters entertain a Leipzig side struggling in the Bundesliga under new boss Jesse Marsch.
They lie eighth in the German top flight with only three wins in their eight games.
Despite their middling domestic form, the PSG defender Presnel Kimpembe said his teammates would have to be on their guard against a team noted for its counter-attacking abilities.
“Even if Leipzig are bottom of the pool we know it’s going to be a tough match,” added the France international.
“Everyone said it would be easy at Bruges but we only came away with a draw. On Tuesday night we’re playing at home and we want to play well.”
While Pochettino will be unable to deploy his star forward Neymar – out with an adductor injury – Marsch will be able to field his lead striker Christopher Nkunku.
The 23-year-old Frenchman spent nine years at the Parc des Princes winning three Ligue 1 titles before leaving for Leipzig in 2019.
“He’s a great player with lots of qualities,” said Kimpembe of his compatriot.
“I know this because we went through the PSG youth academy together. He’s really developed and he’s got the opportunity to show his abilities on the biggest stage.”
The attention though will be on the hosts who will be expected to dazzle with Messi.
He missed Friday night’s 2-1 scrape past Angers in Ligue 1 along with Di Maria and Marquinhos after returning on Thursday from South American qualifiers for the 2022 World Cup in Qatar.
“The situation in our group is simple: we need points,” said Marsch ahead of the clash.
“PSG are a great team with perhaps one of the best attacks in the world – even if it’s still a work in progress. We will have to play as a team and concentrate at all times.”Internet Explorer Channel Network