Goals from Eden Hazard and Diego Costa ensured a fourth straight Premier League victory for the Blues.
And it also means they haven’t conceded a goal in the top flight since switching to a 3-4-3 formation.
“They play a brand of football which won’t be everyone’s cup of tea,” Souness told Sky Sports. “But that was a near-perfect performance away from home.
“No one comes to Southampton and has an easy ride, but Chelsea nullified them”
Liverpool legend Graeme Souness
“They’re happy with that back three – a back five when they don’t have the ball – to sit there and say ‘come on, show us what you’ve got’, and they’re dealing with whatever is being thrown at them.
“It’s counter-attacking football and that’s very Italian, and when I played in Italy, we would be shocked after losing games 1-0 despite having most of the ball.
“That’s the feeling teams will have when playing this side.”
Next up for the Blues in the Premier League is a home clash against Everton on Saturday.