Tom Daley is out of the men's 10-meter platform competition at the Olympics. After finishing first in the preliminary round with an incredible score of 571.85 on Friday, the openly gay diver scored an abysmal 403.25 in the semifinal, leaving him dead last of 18 divers. Only the top 12 advance to the final later today.

His performance today will leave many wondering, "What the hell happened?" To put it in other terms, this is like the Green Bay Packers putting up 48 points on the Bears one week, then scoring only a couple field goals the following Sunday against the Vikings. It doesn't happen without something going terribly wrong.

Of all 18 divers the entire day, only four dives failed to score a 55.00. Daley performed three of those four dives. He needed a score of over 100 on his final dive to advance; Instead he put up a 50.40.

Was it over-confidence after his spectacular performance on Friday? That happens with the best of athletes, posting a personal best then turning around the next morning and flubbing the performance. Is there some of that element here? It's possible. Again, it happens to everyone at some point.

Was it all the attention he suddenly received overnight? Doubtful. Daley has been doing this for a long time, as he discussed in a great spot on NBC that aired Friday night. It's hard to believe this guy let the pressure and attention get to him.

Apparently Daley's fiance, screenwriter Dustin Lance Black, rewarded his boyfriend after every successful round of diving with a chocolate bar. Maybe Daley is just tired of chocolate?

Daley explained it in a way that a lot of athletes can understand. Sometimes you just don't have the hot hand:

I truly am heartbroken, because I really do feel I'm in peak physical condition, and I could have gone out there and won tonight. It's really hard to accept how it went today.

When I'm up on the board, I'm completely present in the moment; today things just weren't clicking. I was giving it my all, I was so up for it today – training beforehand was really good, but in the competition it just fell apart.

It didn't feel any different, I guess my mind and body weren't connecting. I knew I had a shot on the last dive still, and I gave it my all, it just didn't happen today.'

Whatever the reason, fans will be shaking their heads, and the diving world will be long questioning how Daley, who finished with a bronze in London and looked like a solid bet for at least a top-five finish in the final, finished last in the semifinal.

Still, at only 22 years old, Daley is already thinking ahead to the 2020 Olympics in Tokyo. Hopefully he can put today behind him, go win some World Championships and bring him an Olympic gold in four years.