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This is a key game for England. A win will move them closer to qualification for the quarter-finals, but a defeat will leave no margin for error in their remaining games against Bangladesh and Afghanistan.

Former England spinner Graeme Swann has been here before with his country and he has been speaking to BBC Sport about what the current side need to do to avoid an ignominious early exit. Let's start with his thoughts on England's best line-up:

"Unfortunately for Gary Ballance, he's struggling for form and so I wouldn't play him," says Swann. "Other teams have shown that aggressive play at the top can really reap the benefits and England have one of the most aggressive batsmen in the world in Alex Hales. He should be in at the top of the order."

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Sri Lanka didn't exactly come into this tournament hot, having been comfortably turned over by New Zealand in their one-day series, and that patchy form continued with a comfortable loss to the Kiwis in their opening match.

But they've bounced back well, albeit against limited opposition, seeing off Afghanistan after a pretty major scare and then skelping Bangladesh in a highly impressive performance.

Plus points so far: destructive opener Tillakaratne Dilshan is coming into some form - in fact all the front-line batsmen have scored runs so far. Unheralded quickie Suranga Lakmal has bowled rather nicely. Minus points: talismanic spin-merchant Rangana Herath hasn't quite been at his best, and they've had a couple of injury blows: all-rounder Jeevan Mendis has followed Dhammika Prasad in withdrawing.

For the forgetful or plain masochistic among you, a potted resume of England's World Cup campaign so far.

Eoin Morgan's men got off to a rocky start against Australia, conceding 342 runs and then getting rolled for 231 in an ignominious 111-run defeat.

If the margin of that defeat wasn't humiliating enough to indelibly etch itself on your psyche, the subsequent shellacking against New Zealand certainly was. Skittled for 123, then pummelled to all parts by Brendon McCullum. All over in 12.2 overs. Enough to keep you in nightmares for the next 10 years.

But hey, they did at least avoid the considerable banana skin presented by Scotland, easing to a 119-run win in a relatively competent performance.

Plus points so far: Moeen Ali and James Taylor have batted well, in patches. Chris Woakes has acquitted himself quite well with the ball. Minus points: the form of captain Eoin Morgan, the travails of Stuart Broad and a continuing uncertainty about the team's best line-up.

Mike Gardner: If Alex Hales isn't starting tonight, it's an early night for me!

Sleep well Mike!

Stephan Shemilt
BBC Sport in Wellington

"It's a different Cake Tin to the one that saw England destroyed by New Zealand. A week ago, taxis couldn't get close to the ground for the amount of traffic in Wellingon. Today, I've barely bumped into anyone on my walk to the ground. Geoffrey Boycott, who I had to escort to the commentary box, reckons there will be 6,000 in attendance."

England XI: Moeen Ali, Ian Bell, Gary Ballance, Joe Root, Eoin Morgan (capt), James Taylor, Jos Buttler (wk), Chris Woakes, Stuart Broad, Steven Finn, James Anderson.

Sri Lanka XI: Lahiru Thirimanne, Tillakaratne Dilshan, Kumar Sangakkara (wk), Mahela Jayawardene, Angelo Mathews (capt), Dimuth Karunaratne, Dinesh Chandimal, Thisara Perera, Rangana Herath, Lasith Malinga, Suranga Lakmal.

Si Lomas: Unchanged again, how uninspiring and stubborn, no doubt we'll get 270 think we've done well then realise we were 50-60 short.

England are unchanged, with Gary Ballance keeping his place at number three despite a dodgy run of scores. Alex Hales and Ravi Bopara remain on the sidelines for the time being.

Sri Lanka are also unchanged. Batsman Upul Tharanga joined up with the squad following an injury to Jeevan Mendis, but he doesn't get a chance just yet.

England captain Eoin Morgan: "It looked a good wicket the other day [when England played New Zealand at Wellington]. If it does swing, it won't be a surprise but hopefully we play better. We've been out of the traps late but hopefully the Scotland game will give us momentum."

Sri Lanka captain Angelo Mathews: "I'd have batted first too, but the wicket should help the fast bowlers and we'll look to exploit that early on. We played good cricket in our last games and hopefully we can peak from here onwards."

England have won the toss and skipper Eoin Morgan decides to bat first.

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The last time I was on cricket live text duty, Brisbane was experiencing a rainstorm of biblical proportions and we all spent a wonderful four hours waiting for the match between Australia and Bangladesh to be officially abandoned as the night gave way to morning and our will to live slowly ebbed away. Happy days.

Happily, the forecast is looking much brighter for Pakistan v Zimbabwe, which should be getting under way at the Gabba at around 03:30 GMT. That one could be a right royal dogfight, with both teams really needing to win to keep alive their hopes of qualifying for the knockout stages.

We'll be concentrating our attention on England, but we will bring you regular updates from that intriguing Pool B clash later on.

'What are the implications of this group-stage contest?' I hear you cry, your appetite for sharp-end permutations entirely undimmed by the fact that the knockout stages of this tournament are still almost three weeks away.

Well I'm glad you asked. England and Sri Lanka have lost all their matches against top-tier opposition so far (England to Australia and New Zealand, Sri Lanka to New Zealand). So whoever loses here will be unlikely to finish in the top three of Pool A, meaning that they'd be looking at a tricky quarter-final match-up against the winners of Pool B (looking likely to be India) - and they'd still have their work cut out to make it out of the group at all.

Sri Lanka are in a slightly stronger position than England, having won two out of their three matches to England's one, but whoever wins here can feel pretty good about their prospects of making the knockout stages.

Hello and welcome to our live coverage of day 16 of the 2015 Cricket World Cup.

On the menu tonight: match number four for England, who take on Sri Lanka in Pool A in Wellington. Eoin Morgan and Angelo Mathews will stride out to middle for the toss in around 10 minutes' time.

Later on, there will also be a bit of Pool B action to bring you - more on that later.

Outclassed by the Aussies...

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No match for New Zealand...

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But superior to Scotland...

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England have certainly generated plenty of headlines in this World Cup, but so far they've arguably not told us much we didn't already know.

We might have suspected they'd be humbled by the world's best sides on home turf, and let's be honest, you didn't really think they'd be beaten by Scotland's band of county rejects and part-timers - did you?

But tonight we might just get the measure of Eoin Morgan's men. A match against a middle-ranking Sri Lanka side - formidable, but by no means unbeatable opposition - will tell us just where England are at, and how much chance they have of making an impression at this tournament. We might be surprised, we might be disappointed, but in a few hours' time, we'll have a much better idea of just how good England really are.