Barton has previously been outspoken about Hughes after the pair worked with each other at Queens Park Rangers, and the midfielder maintains a negative opinion of the 54-year-old.
The Englishman has suggested that he would not be surprised to see Hughes lead the Saints to safety in the Premier League, but says that his former boss is fortunate to be given an opportunity at St Mary's.
The 35-year-old told talkSPORT: "I saw Mark Hughes appointed and I was surprised. Whichever way you want to dress it up about his record standing up, I don't necessarily agree with that; I don't agree with it based on his tenure at QPR which was, let's be honest, abysmal.
"The back end of the Stoke job, again it was abysmal. Stoke are planted in the bottom three because of Mark Hughes. He's a very very lucky man. Southampton are in a bad spot at the moment but they're massively under-performing so it wouldn't take much to turn that squad around because I do think the previous manager was awful, he was horrific.
"He may well turn Southampton around, but for me, he's a really, really, really poor manager; that's my experience of him."
On Sunday afternoon, Hughes guided Southampton through to the FA Cup semi-finals in his first game in charge, with the south coast outfit beating League One side Wigan Athletic.