And that is the end of this live page on a great day for Leicester - to finally dismiss any fears they could be relegated.
For Watford though, they are still nervous.
Marc Albrighton adds a third goal in injury time after he collected Jamie Vardy's pass and shot into the net.
A hopeful ball is played into the Leicester penalty area, but Foxes goalkeeper Kasper Schmeichel does well to clutch the ball and end any danger.
With Hull losing, Watford are very, very close to securing their Premier League survival. They will be glad they don't have to rely on picking up any more points as their last three games are against Everton, Chelsea and Manchester City.
Andy King looks for Jamie Vardy but the cross is overhit and the chance is wasted.
Anyway back for Watford?
Off goes goalscorer Riyad Mahrez for Leicester, with Demarai Gray getting a run-out.
A good spell from Watford. M'Baye Niang and Tom Cleverley are both denied by Kasper Schmeichel in quick succession, before Schmeichel tips a well-struck effort from Cleverley over the top.
Some good news for Watford fans as Hull have gone 1-0 down at home to Sunderland.
Watford still aren't mathematically guaranteed to finish above Hull, but have a far superior goal difference compared to Marco Silva's side.
Swansea, who are currently 18th, also have to win all three of their games to also overtake Watford.
Leicester's Christian Fuchs goes close with a free-kick, but his 25-yard effort whistles over the bar.
BBC Sport app users may need to click on the below link.
Watford are all over the place here. Riyad Mahrez leads the charge down the right flank, cuts inside and squares it to substitute Islam Slimani, who leans back on the shot and over the top it goes.
We haven't seen much of Watford this half.
Nearly a third for Leicester. Jamie Vardy cuts inside the struggling Adrian Mariappa and blasts low at the Watford goal but Heurelho Gomes can get his body behind the ball and pushes it to safety.
Changes for both sides. Leicester's Andy King comes on for Danny Drinkwater. Islam Slimani had replaced Shinji Okazaki moments earlier.
Etienne Capoue is off for Watford and Troy Deeney is on in his place.
Leicester are on the hunt for more goals here. Watford need to push forward if they are going to have any hope of pulling this one out of the fire.
Thomas Hollern: Vintage stuff from Leicester? It was only last season yet it feels so long ago.
And that could well be the game. A long ball forward is flicked on by Leicester's Jamie Vardy, Watford defender Adrian Mariappa fails to clear the danger and Riyad Mahrez is able to run through.
Just before Sebastien Prodl can get there to challenge, Mahrez is able to slide the ball through the legs of Watford goalkeeper Heurelho Gomes from a tight angle and into the net.
Leicester double their lead.
I don't want to worry you Watford fans, but...
We haven't seen too much of Jamie Vardy today but he has a chance early in the second half.
He is released by Shinji Okazaki and his low, left-footed strike is pushed away by Heurelho Gomes, before the goalkeeper gathers at the second attempt.
And we are back under way.
And this is what else is happening in the Premier League today.
Relegation-threatened Hull are picking up a point at home against already-relegated Sunderland.
Chance for Watford.
Stefano Okaka, with his back to goal seven yards out, looks to make something from Nordin Amrabat's header into the danger zone, but can only flick the ball over the top.
So nearly two goals in three minutes for Leicester. Riyad Mahrez, on the edge of the penalty area, shoots at goal, the ball takes a deflection off of Tom Cleverley, loops up over Heurelho Gomes and bounces off the top of the crossbar.
Is that the goal that ensures Leicester's Premier League status?
Marc Albrighton's short corner from the right wing finds an unmarked Danny Drinkwater and his dinked cross causes panic in the Watford defence.
Sebastian Prodl inadvertently flicks the ball on at the near post, Etienne Capoue makes a hash of an attempted clearance and Wilfred Ndidi is in the right place to blast the ball into the net from 10 yards out.
Tom Cleverley is without a goal this season, but has just tested Kasper Schmeichel. The on-loan Watford midfielder is free 20 yards from goal and blasts the ball at Schmeichel's goal, but the Dane shows his good reflexes to keep it out.
I've seen worse 0-0s. This time it is Leicester's turn to mount a charge, with Marc Albrighton finding the overlapping Danny Drinkwater.
But the cross from the left wing is a poor one. With Jamie Vardy waiting in the box, Drinkwater's delivery can only hit the side netting.
Watford's best moment of the game. Leicester's Robert Huth makes a mess of an attempted clearance and the ball falls to Stefano Okaka.
The Italian, without a goal in two months, takes a touch to set himself and shoots low on the turn, but goalkeeper Kasper Schmeichel, linked with a move away from the Foxes, does well to block the strike with his legs.
We nearly had an own goal minutes ago, and Watford again almost score into their own net.
And this one would have been a cracker. Christian Fuchs' cross from the left wing is met by defender Christian Kabasele, whose diving header is heading into the far corner.
Luckily for Kabasele and Watford, goalkeeper Heurelho Gomes is paying attention, diving to push away Kabasele's header and save his team-mate's blushes.
So close to the first goal of the game. Jamie Vardy is free in the penalty area from a quickly-taken free-kick by Riyad Mahrez and his low cross causes panic in the Watford defence and Adrian Mariappa diverts the ball on to his own post.
Mariappa had to do something as Shinji Okazaki was waiting to pounce, but with goalkeeper Heurelho Gomes well beaten, Mariappa is an extremely lucky man to see the ball bounce back off the upright.
Watford's Stefano Okaka, who is wearing gloves - in May - is going to make it a tough day for the Leicester defence. He bustles and bumps Robert Huth, but the centre-half, with a bit of help from some team-mates, is able to eventually clear the danger.
Should do better.
Watford's Tom Cleverley, in the middle of the goal at the top of the 'D', is played a square pass but the curled effort is going wide from the moment it left his boot.
Lots of chances for both sides, but neither goalkeeper tested so far.
An enjoyable start at the King Power Stadium, with both sides looking lively.
It is Watford's turn to attack and only some excellent defending from Yohan Benalouane, who does well to dive in and stop a right-wing cross, denies Stefano Okaka what would have been a good chance.
A corner to Leicester is swung in by Marc Albrighton and Watford goalkeeper Heurelho Gomes does well to punch it away under pressure from Wilfred Ndidi.
The ball falls to Danny Drinkwater, on the edge of the penalty area, but the England international can only shoot harmlessly over the top.
A bright start from both sides. Leicester's Riyad Mahrez, on the right wing and with two defenders backing off, produces a stepover to create some space for the cross, which he delivers to the back post. Watford's Christian Kabasele spectacularly heads it behind for a corner, which comes to nothing.
An early chance for Watford as M'Baye Niang releases Daryl Janmaat in the penalty area, who looks to curl one at goal.
But, let's be honest here, that is a rubbish attempt, with the ball going well, well wide.