The former Reading shotshopper is set to be a free agent next summer but has played every minute in the Premier League this season and is Ralph Hasenhuttl's first-choice between the sticks.
What's the latest news with McCarthy?
McCarthy has generally been Saints' number one goalkeeper since he arrived from Crystal Palace back in 2016, although he briefly lost his place in the side to Fraser Forster last season.
He had played 90 minutes in 24 of the first 25 Premier League games last term, the exception being the 1-0 victory over Liverpool in January that he missed after testing positive for Covid.
However, McCarthy paid the price for a poor performance at Leeds in late-February and would find himself in and out the team from then on in, regularly rotating with Forster.
McCarthy, though, did reclaim his spot towards the end of last season and has quickly dusted off the mistakes to consolidate himself as Saints' first-choice keeper.
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The 31-year-old's deal on the South Coast is set to expire in the summer of 2022, meaning he could essentially leave for nothing.
But Barclay is confident that McCarthy will sign fresh terms at St Mary's having recently told the Daily Record that he's enjoying his football.
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What did Barclay say?
He told GIVEMESPORT: "I know they were in contract negotiations last season and that it didn't really happen, and he fell out of favour for Forster. But it's likely to happen again soon. In that interview with the Daily Record, he was saying how happy he was and settled down there."
Does McCarthy deserve a new deal?
His time with Southampton has been up and down to say the least. As mentioned above, he's generally been number one, but has found himself in several battles to keep his place, not least his ongoing one with Forster.
But McCarthy, valued at £4.5m by Transfermarkt, is winning that battle, and based on this season alone, Saints would be daft not to keep him around.
The stats suggest that, too, because according to WhoScored, he's been the fourth best keeper in the Premier League this season, behind only Edouard Mendy, Allisson, and Aaron Ramsdale, with an average rating of 6.90.News Now - Sport News