The champions remained nine points behind Manchester United after a comedy of errors saw them lose 3-1 at St Mary's on Saturday.

Sir Alex Ferguson's league leaders will go 12 points clear if they beat Everton at Old Trafford on Sunday, and Mancini is resigned to his team losing their Premier League crown.

He told ESPN: "I think now we have a 10 percent chance maybe. I don't think that we'll recover 12 points; it will be really difficult."

Mancini also felt the performance against Southampton was one of the worst in his time at the club and bemoaned the absences of injured captain Vincent Kompany and Matija Nastasic.

Asked what he said to his players after the match, the Italian added: "Nothing. I think they understand that we played really badly. I think this the worst game in the last two or three years.

"We're missing Vinnie (Kompany), we're missing Nastasic, and we have some players who are not in form because they played really badly; without strength, without personality, and I'm disappointed with them."

Saints striker Rickie Lambert said despite the horrendous City defending, the home side were worthy of the three points.

"I think it's our best performance (of the season)," Lambert said.

"We were absolutely superb today and got exactly what we deserved.

"We looked for the early goal and looked to put them under pressure early and hope to capitalise on it. It worked perfectly. Then we went 2-0 up, which was even better."