Serena Williams: Five awkward sporting moments

World tennis champion, Serena Williams, had a really awkward moment at the Australian Open.

When her opponent, the current world number one - Simona Halep - was called to the court, Serena appeared instead.

Having spent more than 300 weeks as the world number one, it's no real surprise she made the mistake.

But, it made us think, what are the MOST awkward sporting moments of all time? Here's some of our favourites...

1. Gary Lineker

No-one wants to see a middle aged man in his pants. Do they? Well apparently they do. Back in 2016, one of the most unlikely football title races was taking shape in the Premier League. Tottenham were taking on Leicester - a team who had only just avoided relegation a year before.

Boyhood Leicester fan, and Match of the Day presenter, Gary Lineker couldn't resist posting a cheeky tweet to show his support. He tweeted following Leicester's 2-1 win against then champions Chelsea, a victory which moved the leaders two points clear after 16 games.

Leicester pulled off the impossible by winning the Premier League title and Lineker kept his promising by pulling off his clothes. You can see the result below (if you want).

Gary Lineker keeps his promise and wears his pants during Match of the day.

2. Tim Henman

Tim Henman apologises to ball girl after hitting her with a tennis ball during a match at Wimbledon.

Tim Henman isn't really known for having a temper. Instead, he's known for having his own hill at Wimbledon and, before Andy Murray, as being Britain's only tennis hope. But, back in 1995 he hit the headlines for all the wrong reasons.

During a Wimbledon doubles match, Henman lost his temper and whacked a ball away in frustration. He didn't realise it at the time but his stray ball had hit a ball-girl right in the face. It had been travelling at 92 mph when it hit her.

Henman was instantly disqualified from the competition, becoming the first player since 1968 to do so. Luckily though, the girl was fine and Henman apologised with a bouquet of flowers the next day.

3. Jon Drummond

Jon Drummond (left) is disqualified after false starting in the 2003 World Championships.

In the late nineties and early noughties, Jon Drummond was a really good 100m sprinter. He'd been part of the gold medal winning USA relay team at the 2000 Sydney Olympics.

In 2003, Drummond was disqualified for a false-start in the quarter-finals of the World Championships. However, Drummond didn't think he'd false-started. In fact, he was adamant he hadn't false-started.

Jon Drummond stayed on the track for a whole hour!

He refused to leave the track and lay down on the ground. He stayed on the ground for an hour and held up the whole competition while stewards attempted to get him to move.

4. Three card wonder

English referee Graham Poll showed Croatian defender, Josip Šimunić

If you're a referee the ultimate game to officiate has to be the World Cup Final. Back in 2006, English referee Graham Poll was in with a shout of doing it. He was one of the most high profile referees in world football and he was England's only official at the tournament. So, a group game match between Australia and Croatia shouldn't have been a problem, should it?

Unfortunately for Graham Poll, life doesn't always work out that way. He managed to give Croatian defender Josip Šimunić THREE yellow cards before sending him off, instead of the two he should have given. He was sent home shortly after and never appeared at a World Cup again.

Josip Šimunić was given three yellow cards by English referee Graham Poll

5. It's not the first awkward Serena moment!

Imagine what it feels like to beat Serena Williams at tennis. And, imagine doing it at just 20-years-old in a Grand Slam final! That's what happened to Japanese player Naomi Osaka at last year's US Open final. Unfortunately for Osaka, the headlines weren't about her. Instead, they were about Serena Williams' on-court meltdown.

In the match Williams wasn't happy with the decisions of the umpire, Carlos Ramos. He thought she was being coached, which is against the rules during a game. She accused him of being a 'thief', screamed at him and smashed her racket on the court.

During the trophy presentation both players were crying and the crowd were booing.

Former Wimbledon champion Pat Cash said it was "the most bizarre match and presentation" he'd ever seen.