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Australia win by five wickets to pick up first victory
They chase 210 with 14.4 overs to spare
Australia were 24-2 after Madushanka traps Warner & Smith lbw in fourth over
Inglis adds 58, Marsh 52 & Labuschagne 40
Sri Lanka slip from 125-0 and 157-1 to 209 all out
Leg-spinner Zampa improves from poor first spell to take 4-42
Australia's chase of 210 was delayed by rain and over safety concerns for players and spectators due to sand storm and high winds
Part of stadium branding and temporary structures came down during SL innings but no injuries, say ICC
Right, that's all from Lucknow.
Take a read of Stephan Shemilt's report and join us tomorrow for South Africa v Netherlands from Dharamsala. It's a 9:30 BST start, and we'll have commentary and clips as usual.
Have a good evening.
Marsh and Labuschagne eventually departed, but Josh Inglis passed fifty before Glenn Maxwell and Marcus Stoinis arrived to finish the innings with some explosive hitting.
The second innings also started well for Sri Lanka as Dilshan Madushanka removed David Warner and Steven Smith within one over.
But Mitchell Marsh struck 52 at just over a run a ball, while Marnus Labuschagne dropped anchor in the middle-order.
Perera put on 32 with Kusal Mendis before he was bowled by Cummins. A mighty collapse followed, as Sri Lanka lost all ten wickets for 84 runs.
Charith Asalanka - the last batter to fall - was the only batter outside the openers to reach double figures.
It all started so well for Sri Lanka!
Winning the toss and choosing to bat, their opening partnership of Pathum Nissanka and Kusal Perera put on 125 for the first wicket, before the former was caught in the deep off Pat Cummins.
Carlos Brathwaite
Ex-West Indies all-rounder on BBC Test Match Special
It was the fielding efforts of Glenn Maxwell and David Warner that really shifted things for Australia today. Their energy and their high standards ensured that they turned things around after Sri Lanka's opening partnership.
If Australia go on in this tournament, we will look back at those two today as being the turning point.
Australia captain Pat Cummins: "Yes, I'm happier today!
"We didn't say much before the game, but after two losses we wanted to get back to where we know we can be with our high standards.
"Their openers started really well and we were staring down the barrel of a big score. But we stuck together, all our bowlers did their job and to finish it off for 209 was a great effort.
"I'm not very good at reading these wickets but I would say something close to 300 would have been a par score.
"The outside noise doesn't bother us too much. We know what we can do as a squad.
"I hope that this result can kick us forward. All three aspects of the game came together today and we need to keep that up."
Here's the mighty six from Marcus Stoinis that saw Australia home with five wickets to spare.
Sri Lanka captain Kusal Mendis: "First of all, congratulations to our opening partnership. But after that our top and middle-order were struggling, that's why I think we ended up getting the lower score - I think 290 or 300 would be defendable.
"Last two games we batted really well. Today a little bit of a struggle. We have six more matches where we can do better than today. I have confidence in our batting unit.
"I think Madushanka bowled really well, taking early wickets. I hope our injured players recover quickly. Some should be available to play in the next match."
Player of the Match, Australia's Adam Zampa: "I didn't feel great. I have had trouble with back spasms over the past couple of days so it was just about trying to get through that one.
"I've had days where I've felt better and bowled better. Personally I know I'm not at my best, but it's nice to be on this end of the result tonight.
"I've just got to try and keep my wicket-taking attitude because that's what works for me, regardless of whether I am going for runs or not.
"We've got a tough game coming up next against Pakistan but I am going to try and keep things the same for me."
Carlos Brathwaite
Ex-West Indies all-rounder on BBC Test Match Special
It wasn't a win where everything fell into place. It wasn't fluent, it wasn't a typical dominant Australia win but they got there, and those points on the board are all that matters.
There will be a feeling of relief in that team. With Sri Lanka 100-0, it was looking like another defeat but they fought really hard in the middle overs to get themselves back in it.
Australia move off the bottom of the table and now sit in eighth, with one win from their three games.
They leapfrog ninth-placed Sri Lanka, who along with the Netherlands are yet to notch a win in this tournament.
Carlos Brathwaite
Ex-West Indies all-rounder on BBC Test Match Special
Australia will take a lot of heart from this performance, particularly how they fought back with the ball.
Form for Josh Inglis will also be a positive, but there is still some work for the top-order batters to do. However, they may just start to peak at the right time.
Nikesh Rughani
BBC Test Match Special commentator
That is a hugely important win for Australia. They stay alive in this World Cup.
Well, these two weren't going to finish it with a single, were they?
It's Stoinis who gets to end it, shifting in his crease and crashing Wellalage down the ground for six with a great, sweeping arc of his bat.
It's a first win in the tournament for Australia, while for Sri Lanka it's three defeats from three.
It won't happen this over - and it's perhaps right that it doesn't happen off Madushanka's bowling, he's outshone his teammates in this second innings.
Three more singles, the last punched down the ground by Stoinis and the scores are level.
Maxwell takes a single into the covers before Stoinis finds two in the leg side.
A Madushanka wide sees Australia four runs away from victory.
Geoff Lemon
BBC Test Match Special commentator
The last runs are coming very quickly from the bat of Marcus Stoinis.
8 runs needed from 92 balls
Marcus Stoinis arrives, meaning arguably Australia's two biggest hitters are at the crease.
You'd be right to expect a quick conclusion - Stoinis smacks his first ball for four, rolling his wrists to keep the sweep down but the ball still only bounces once as the ball scuds to the boundary.
He then brings up the Australian double century with four more from a powerful cut shot.
Carlos Brathwaite
Ex-West Indies all-rounder on BBC Test Match Special
It's the first loose shot from Josh Inglis in a while. He was trying to hit it over extra cover but he looked a bit deceived by the flight.
It is a well-deserved wicket for Dinuth Wellalage.