text: The home side almost went behind when Charlie Austin went close with two headers and hit the post with a shot.
  Austin was also through on goal in the second half but an ambitious chip was saved by keeper Kasper Schmeichel.
  Jamie Vardy had Leicester's best chance after a poor backpass but he was tackled by Oriol Romeu, who also blocked two follow-up shots.
  The Foxes have now won only two of their opening seven leagues games, collecting eight points.
  Relive all the action and reaction to Sunday's games
  Leicester are now unbeaten in 19 Premier League home games since a defeat by Arsenal in September 2015 but that record would have been ended if Southampton's finishing had been more clinical.
  The Foxes had gone into the game following another impressive win in the Champions League - 1-0 over Porto on Tuesday - but they failed to replicate that form, with the visitors having the better chances as the home side managed just one shot on target.
  Vardy had the type of opening he relishes when he ran on to Virgil van Dijk's poor backpass but he tried to round keeper Fraser Forster and gave Romeu enough time to get back and tackle him.
  The two shots in the aftermath from Islam Slimani and Vardy, who has failed to score in six games, were also blocked by the Southampton midfielder.
  An effort that came from a clutch of bodies following a Christian Fuchs cross almost crept in at Forster's near post and Shinji Okazaki nodded just wide but, whether it was because of their Champions League exertions in midweek, the Foxes rarely carried the threat that won them the top-flight title last season.
  Southampton's build-up to the game had been overshadowed by assistant manager Eric Black being named in a Daily Telegraph investigation into corruption in football and a seven-hour delay in their return from a Europa League tie in Israel on Thursday.
  But manager Claude Puel made seven changes for the game at the King Power, and they started strongly as Austin had one header saved and glanced another wide before seeing an acute-angled shot coming back off the far post.
  Austin had scored five goals in four games going into the match and should have added to that tally when he was through on goal in the second half only to go for a difficult chip over Schmeichel, which was saved.
  Their main concerns at the back came from their own mistakes, especially Van Dijk's weak backpass, but they comfortably kept their sixth successive clean sheet in all competitions.
  Leicester manager Claudio Ranieri: "I'm very happy because Southampton deserved to win. They played better. We conceded too many chances to score a goal.
  "I recognise they played better than us. Fortunately we finished with a draw from the match."
  On playing Champions League games in midweek: "Everything is a new experience. Now I have to decide whether to give a rest to players."
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  Southampton boss Claude Puel: "We had the possibilities to win the game. It is a little disappointing at the end of the game because I thought we could have won.
  "It is positive for the future. It is important for the squad to take confidence."
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  Leicester City's next game takes them to manager Ranieri's former club Chelsea for the 12:30 BST game on Saturday, 15 October. Southampton host Burnley at 16:00 BST the following day.
  Match ends, Leicester City 0, Southampton 0.
  Second Half ends, Leicester City 0, Southampton 0.
  Attempt missed. Leonardo Ulloa (Leicester City) right footed shot from outside the box is too high. Assisted by Daniel Drinkwater.
  Attempt blocked. Oriol Romeu (Southampton) right footed shot from outside the box is blocked.
  Offside, Southampton. James Ward-Prowse tries a through ball, but Shane Long is caught offside.
  Offside, Leicester City. Christian Fuchs tries a through ball, but Leonardo Ulloa is caught offside.
  Foul by Nathan Redmond (Southampton).
  Daniel Amartey (Leicester City) wins a free kick in the defensive half.
  Pierre-Emile Højbjerg (Southampton) wins a free kick in the defensive half.
  Foul by Daniel Drinkwater (Leicester City).
  Attempt missed. Cuco Martina (Southampton) left footed shot from the centre of the box is too high.
  Substitution, Southampton. James Ward-Prowse replaces Charlie Austin.
  Virgil van Dijk (Southampton) wins a free kick in the defensive half.
  Foul by Leonardo Ulloa (Leicester City).
  Foul by Nathan Redmond (Southampton).
  Riyad Mahrez (Leicester City) wins a free kick in the attacking half.
  Pierre-Emile Højbjerg (Southampton) wins a free kick in the defensive half.
  Foul by Daniel Drinkwater (Leicester City).
  Corner,  Southampton. Conceded by Robert Huth.
  Substitution, Leicester City. Leonardo Ulloa replaces Islam Slimani.
  Ryan Bertrand (Southampton) wins a free kick on the left wing.
  Foul by Riyad Mahrez (Leicester City).
  Attempt missed. Shinji Okazaki (Leicester City) header from the centre of the box is close, but misses to the right. Assisted by Demarai Gray with a cross.
  Islam Slimani (Leicester City) hits the left post with a header from the left side of the six yard box. Assisted by Christian Fuchs.
  Substitution, Southampton. Shane Long replaces Dusan Tadic.
  Oriol Romeu (Southampton) wins a free kick in the defensive half.
  Foul by Shinji Okazaki (Leicester City).
  Attempt saved. Pierre-Emile Højbjerg (Southampton) right footed shot from outside the box is saved in the bottom left corner. Assisted by Steven Davis.
  Attempt saved. Daniel Drinkwater (Leicester City) left footed shot from outside the box is saved in the centre of the goal. Assisted by Christian Fuchs.
  Corner,  Leicester City. Conceded by Steven Davis.
  Foul by Charlie Austin (Southampton).
  Danny Simpson (Leicester City) wins a free kick in the defensive half.
  Substitution, Leicester City. Shinji Okazaki replaces Jamie Vardy.
  Substitution, Leicester City. Demarai Gray replaces Marc Albrighton.
  Attempt missed. Daniel Drinkwater (Leicester City) left footed shot from a difficult angle on the left is close, but misses to the left. Assisted by Marc Albrighton.
  Attempt saved. Charlie Austin (Southampton) right footed shot from the centre of the box is saved in the top centre of the goal. Assisted by Virgil van Dijk with a through ball.
  Attempt saved. Nathan Redmond (Southampton) right footed shot from the centre of the box is saved in the bottom right corner. Assisted by Pierre-Emile Højbjerg.
  Foul by Charlie Austin (Southampton).
  Islam Slimani (Leicester City) wins a free kick in the defensive half.
  Corner,  Southampton. Conceded by Daniel Drinkwater.
target: Champions Leicester City's struggles in the Premier League continued as they were held to a draw by Southampton.