Southampton suffered relegation last season after finishing bottom of the Premier League table.
And Saints appointed former Swansea City boss Russell Martin to take them back to the Premier League at the first time of asking.
However, Southampton have suffered two back-to-back heavy defeats against Sunderland and Leicester City, conceding nine goals in two matches, which has made Nugent think that Saints are playing in a style they are not good at.
The former Leicester City striker added that Southampton look like they have been playing in the Championship for a couple of years if compared with Leicester City and added that he would be worried if he were a Southampton fan.
“It just shows the level between the two sides for me“, Nugent said on BBC Radio Leicester.
“Obviously both teams got relegated from the Premier League, but if you compare the game today, you would think Southampton have been in this league for a couple of years.
“They are playing in a style of play that I do not think they are good enough to do.
“You can see why they are conceding goals, they score a lot of goals, but they concede so many more.
“If I were a Southampton fan, I would be worried.”
Southampton are seventh in the league table with ten points from six matches and they are set to face Ipswich Town on Tuesday.
