After the champagne sparkle of Leicester's historic Champions League night, this was the annoying hangover.
Claudio Ranieri and his players were always going to struggle to produce an encore to their stirring victory over Porto on Tuesday and this excruciating afternoon continued the champions's unpredictable defence of the title.
Leicester have now recorded 19 Premier League games at home without defeat, but they could easily have surrendered that proud record against a vibrant Southampton, who are improving rapidly under Claude Puel. The v-isitors wasted many chances to become the first team since last September to raid the King Power Stadium, while their defence have now gone nine hours without conceding a goal.
Gareth Southgate, the England caretaker manager, will have learnt little watching from the stands. Leicester were strangely lacking in stardust, perhaps feeling the after-effects of the first Champions League home game in their 132-year history. "It's a new experience, adapting after the Champions League," Ranieri said. "Maybe I have to think about when we play every three days, we should maybe have given some players some rest.
"Southampton played better than us and they deserved to win - we have to recognise this. Kasper S-chmeichel made some very good saves to keep us the clean sheet.
"The other teams are very -worried with our counter-attacking and we have to find the solution. We have to continue to work."
Southampton's week has been far from easy, after assistant manager Eric Black was named in The Daily Telegraph's investigation into claims of corruption, yet Puel should have been celebrating his first win in four games against Ranieri. It was Puel who had feared tiredness would afflict his players, after their trip to Israel for Thursday's Europa League tie, but it was Leicester who lacked energy.
Charlie Austin missed his first opportunity in the ninth minute, heading straight at Schmeichel from a decent position, before striking the post from a tight angle inside the penalty area. While all the attention has been on Southampton's miserly defence, they also possess a potent blend of attacking players - Nathan Redmond was full of guile, while Dusan Tadic was a frequent menace in a free role.
Leicester were laboured and -disjointed, but should have taken the lead on the half-hour, after a gift from Virgil van Dijk. The Dutchman's dreadful back pass presented Jamie Vardy with a clear run at goal, but the striker never looked confident and, though he rounded Fraser Forster, his shot was blocked by Oriol Romeu, with both Islam
Slimani and Vardy then denied again by the Southampton defence.
Puel suffered defeat three times against Ranieri during their battles in the French league, and he cut a frustrated figure in his technical area, constantly wheeling around with his arms in the air.
Yet it was Leicester who were producing more mistakes, and Redmond could have exploited some space in the area but shot tamely at Schmeichel. Austin wasted an even more promising chance in the 63rd, after Leicester's defence again went walkabout, only for Schmeichel to pluck his attempted chip out of the air with ease.
With his team so flat, Ranieri had no option but to make changes
as time ticked away, and Demarai Gray and Shinji Okazaki were introduced in a bid to pose more of an attacking threat. Vardy's withdrawal raised some eyebrows, but -Okazaki -instantly provided a spark, with Danny Drinkwater testing Forster from distance. Forster also kept out Robert Huth's near-post header and the home team were finally clicking into gear. A stalemate was inevitable, though, and Southampton have now gone 540 minutes without conceding a goal.
Puel said: "I think it was positive to leave some players at home when we played in Israel. It's a crazy schedule and we can see the troubles of playing in a European tournament. To have the ability to have a good game like this after a long trip is very interesting."