Garrett Lai

As my bike-racing friend Lucky John says: The Tour de France is a hard mistress. And that point was driven soundly home as we watched Floyd Landis experience a meltdown of Chernobyl proportions on the slopes of Wednesday’s finishing climb to La Toussuire during the 16th stage that ruined his chances to win the race.

The Tour de France is the most physically demanding event imaginable. These guys race more than five hours without ever seeing their heart rates drop below 80 percent of maximum — and they’ll do it again every day, for three straight weeks. If you’re at anything less than 100 percent, the consequences can be dire.

For instance, U.S. cyclist Levi Leipheimer has put in some gutsy, impressive rides during this Tour, but in the individual time trial in stage 7 he was a little off and finished 96th.

The most amazing thing about Tour winning streaks is how much luck is involved. Miguel Indurain’s five consecutive victories were incredible, not just because he was the first five-time winner, but because he never had an off day in more than 100 days of racing.

And Lance Armstrong's streak was even more amazing. In more than 140 racing days during his seven-year win streak, he had only bad day, when he dehydrated in the mountains during the individual time trial in 2003 and lost 96 seconds to Jan Ullrich.

Wednesday was Floyd’s turn to have an off day, and unfortunately, the other guys were poised to take advantage.

The day before, Landis looked unstoppable. He was the only rider who didn’t red-line as he calmly answered every attack. It appeared that his only weakness the rest of the way would be his relatively weak team of Phonak and their limited ability to withstand sustained attacks from T-Mobile and Rabobank.

I didn't think the real weak link would be Floyd himself.

Floyd looked good for most of Wednesday's stage 16, especially considering he was virtually without team support for most of it. Axel Merckx was his lone teammate on the final climbs, whereas T-Mobile's Andreas Kloden enjoyed the company of his pink-suited hit squad, and CSC took good, sustained pulls at the front.

Landis was isolated but never looked to be in trouble. He responded patiently when T-Mobile’s Michael Rogers, Rabobank’s Denis Menchov and Caisse d’Epargne’s Oscar Pereiro surged out of the pack with nine miles left, choosing to wait and let another team (T-Mobile, in an eerily similar replay to last year’s tactic of chasing down their own Alexandre Vinokourov) reel them in.

When CSC’s Carlos Sastre launched with a hard move off the front, in what appeared to be a bit of a Hail Mary, it wasn’t a big deal. Cyclists do this all the time, just to see who’s strong and bears watching. But when T-Mobile massed at the front and upped the tempo Landis was suddenly off the back of the pack. His supple pedal stroke was gone — he stabbed at the pedals, his legs signaling that he was finished, or as TV commentator Phil Liggett says, "cracked."

Landis even left his earpiece dangling —  there was nothing anyone could say to help him.

Under the 10-kilometer banner Landis looked awful, while the race literally moved up the road without him. In fact, when the cameras showed him moving over to let the team cars pass, I really thought he was about to stop and put his foot down and do the unthinkable: abandon the race while wearing the maillot jaune.