Chelsea avenged their FA Cup final defeat by Leicester to move above the Foxes into third in the Premier League with a 2-1 win in front of 8,000 fans at Stamford Bridge on Tuesday.
Antonio Rudiger and Jorginho, from the penalty spot, scored the goals for Thomas Tuchel's men to keep a place in next season's Champions League in their own hands.
However, victory came at a cost for the Blues as N'Golo Kante limped off injured in the first half just 11 days before they face Manchester City in the Champions League final.
Victory away to Aston Villa on Sunday will guarantee Chelsea a top-four finish.
Leicester will forever have the memories of winning the FA Cup for the first time at Wembley on Saturday but are now at risk of missing out on Champions League football on the final day of the campaign for the second consecutive season.
Brendan Rodgers's men still lead Liverpool by three points, but the Reds will go fourth on goal difference if they win at Burnley on Wednesday. Leicester host Tottenham on the final day, while Jurgen Klopp's men welcome Crystal Palace to Anfield.
Roared on by the biggest attendance at Stamford Bridge in over 14 months, Chelsea exploded out the blocks with Leicester barely able to get out their own half in the first 45 minutes.
However, a combination of Kasper Schmeichel and controversial refereeing kept the hosts at bay until the break.
Chelsea was denied in a dramatic end to the cup final by a VAR review which ruled out Ben Chilwell's goal for offside.
Timo Werner had two more goals disallowed in the first half as the German international was firstly flagged offside before his second effort was ruled out by a VAR review for handball.
But in between, Werner was rightly dismayed when he was somehow denied a penalty.
Youri Tielemans's stunning strike was the difference between the sides three days ago, but the Belgian was caught dallying on the ball inside his own box by Werner and kicked the former RB Leipzig striker as he attempted to clear.
Referee Mike Dean bizarrely blew for a free-kick against Werner and was not asked to review his original decision by VAR.
With millions on the line for a place in the Champions League, that decision could have proved very costly for Chelsea.
But there was little doubt about the outcome once Rudiger bundled home a corner two minutes into the second half.
Werner finally got a VAR call to go his way to double Chelsea's lead 24 minutes from time. Wesley Fofana's foul on Werner was initially given as a free-kick outside the box, but on review, Dean was told to point to the penalty spot.
Jorginho coolly sent Schmeichel the wrong way and for 10 minutes, Chelsea looked to be cruising.
However, Leicester set up a nervy finale when Wilfred Ndidi robbed Mateo Kovacic and teed up Iheanacho to slot home his 19th goal of the season. The Nigerian also became the first player to score on all seven days of the week in a single Premier League season.
Leicester had a glorious chance to salvage a point and keep their top-four fate in their own hands in the final minute, but Ayoze Perez blasted over from Ricardo Pereira's cut-back.
Tempers flared in stoppage time with both sets of players, substitutes and coaches involved in an altercation after Rudiger took exception to a challenge from Pereira on Chilwell.
Chelsea, though, kept their heads to see out the final few seconds and take a huge step towards another season of Champions League football.