After Frank Lampard was left peeved by Chelsea’s failure to sign a striker in January, his centre-back Antonio Rüdiger did his best to soothe the manager’s concerns by scoring with two fine headers. But those goals were not enough to close the gap on Leicester, who earned a share of the points thanks to goals by Harvey Barnes and Ben Chilwell. The result leaves Brendan Rodgers’ side relatively comfortable in third place, eight points above fourth-placed Chelsea, who can feel the breath of the chasing pack on their backs.

Last season Chelsea finished 20 points above Leicester, but Rodgers’ team have improved since then and the Londoners have not. Lampard is spooked by the strengthening of other clubs, suggesting the purchases made by Manchester United and Sheffield United make Chelsea underdogs in the fight for the last Champions League qualification spot. “We must be super-underdogs then, given where we were at the start of the season,” quipped Rodgers.

Lampard’s angst cannot have been eased by the profligacy of players other than Rüdiger, especially in a first half in which Chelsea’s lack of sharpness in front of goal prevented them from taking a lead they would have deserved. Several times teasing crosses were delivered into the home box – usually by Callum Hudson-Odoi or the excellent Reece James – but no attacker showed enough instinct and poise to get on the end of them.

Tammy Abraham was full of enthusiasm but was certainly not clinical after being declared fit enough to play despite the ankle knock he suffered in the draw with Arsenal two weeks ago. One wonders what Olivier Giroud made of it all. The Frenchman, denied a January move away, was not even in Chelsea’s squad here.

Kepa Arrizabalaga was dropped to the bench, as Lampard decided that the out-of-form goalkeeper needed a reminder than his No 1 spot is not guaranteed. “We have to be competitive,” said Lampard, who instead gave Willy Caballero his first Premier League start since May.

The 38-year-old must have fancied his chances of keeping a clean sheet here as Leicester made an uncharacteristically sluggish start. Their attempt to show that they were not deflated by their midweek Carabao Cup defeat at Aston Villa suffered a setback even before kick-off when Wilfred Ndidi felt pain in his knee and was replaced in the starting line-up by Hamza Choudhury.

For the first 25 minutes Chelsea practically had the run of the place. César Azpilicueta made regular bursts down the left, virtually unhindered by Ayoze Pérez. But when the left-back supplied an inviting centre in the fifth minute, Hudson-Odoi gave an indication of what was to come from Chelsea’s forwards in the first half by swishing at fresh air from the edge of the area.

Chelsea continued to create danger but their final touch was regularly awry. Leicester woke up in the 25th minute, jolted into action by sloppy play from Chelsea. Azpilicueta played a careless pass that Pérez chested into the path of Jamie Vardy. It was Caballero’s time to shine, the keeper rushing off his line to block the shot from Vardy, who went for power rather than precision.

Leicester came close to taking the lead just before the break, when Choudhury leapt above N’Golo Kanté only to head wide.

Within 57 seconds of the restart Rüdiger did what Choudhury had tried to, taking advantage of hesitancy in the Leicester backline to head in a corner at the back post. If he hoped his attacking team-mates had taken note of his emphatic finish, Rüdiger would soon be dismayed to realise that his goal inspired Leicester. The hosts struck back with two goals in 10 minutes.

Barnes scored the first after being released down the left by Youri Tielemans. The winger also enjoyed assistance from Andreas Christensen, who inadvertently deflected his shot over the wrong-footed Caballero and into the net.

Caballero was caught in the wrong place again in the 64th minute after deciding to chase an overhit cross by Chilwell. The goalkeeper did an about-turn when he realised Ricard Pereira would beat him to the ball but did not get back in position in time to stop Chilwell from swatting a low cross from Tielemans into the net.

Chelsea did not look like equalising until Rüdiger soared above Chilwell to meet a free-kick from the left by Mason Mount and power the ball in from 15 yards.

Jonny Evans had a chance to emulate his centre-back counterpart but nodded wide from six yards after being left free at a corner. Then Barnes was presented with an even better opportunity by Vardy but sidefooted wide from 10 yards.