The much-hyped, long-awaited showdown between Floyd Mayweather and Manny Pacquiao on Sunday morning (3am GMT) is the must-watch sporting event of the year.

This fight is bigger than boxing - every sports fan is currently talking about it. As we type, people across the land are trying to figure out where they can watch the fight of the century.

There's just one problem: staying awake.

Thanks to the joys of the USA-UK time difference, the fight is due to begin at roughly 3am. So, how can you make sure you've not passed out on the sofa before the action even begins?

Luckily, we have spoken to top sleep expert Dave Gibson - the man who runs The Sleep Site - to get his advice on staying up very, very late…

1 Adjust your body clock NOW

"It's important to change your sleep pattern in advance. Go to bed tonight [Friday] as late as possible, and get up as late as possible tomorrow [Saturday].

"Whatever you do, don't wake up early tomorrow. If your blinds or your curtains are a bit rubbish, it's even worth sticking a rug or a thick sheet over your window - whatever it takes to block out the light.

"If you really can't do that, make sure you find time for a nap on Saturday afternoon."

2 Don't burn yourself out

"It sounds obvious, but you have to conserve energy. If you normally go the gym on a Saturday, go on Sunday instead. Don't do anything during the day that will burn you out.

"Remember, you're in a fight too - a fight to stay awake!"

3 Avoid caffeine

"A lot of people will rely on coffee, but during the day, caffeine is your enemy.  

"Caffeine stimulates a receptor in the brain, which means it will be useful at around 3am. At that point, a coffee or a Coke will give you a short-term boost.  

"However, if you drink any caffeine during the day, it could have the opposite effect, as you will have a slump once it's worn off."  

4 Start your party as late as possible

"The simple fact is, if you start drinking at 8pm, there is no way you will be awake at 4am. If you are determined to have a few Saturday night drinks, make sure you have your first one as late as possible.  

"Alcohol works as a stimulant up to a point - however, it becomes soporific [sleep-inducing] once you've had a few.  

"It's also worth thinking about drinking something other than beer. Beer is full of carbohydrates, which makes your blood sugar shoot up - and then drop after, sending you into a slump."  

5 Whatever you do, DON'T order a pizza

"My number one bit of advice would be to not go anywhere near a pizza. Like beer, it's full of carbs, so it will give you that initial sugar rush that sees you fall into a slump shortly after.  

"If you REALLY want a pizza, make sure you don't have it until about 3am. Personally, I'd go for a steak and a baked potato.

That takes a long time to digest, which means it will give you a steady source of energy over a longer period."

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