Here's an interesting one. Major League Soccer today fined the Los Angeles Galaxy $5,000 for violating the league's policy regarding injury reports ahead of their match with Colorado. According to the press release, MLS concluded that the Galaxy deliberately omitted David Beckham's name from the injury report before the Colorado Rapids match despite knowing he would miss the game with back spasms. It's MLS policy that teams send out an injury report twice a week during the regular season and those reports must be as accurate as possible.
The Galaxy went on to win that match against Colorado 1-3, with a Colorado own goal, a Juninho screamer, and a Chad Barrett goal from a Todd Dunivant cross. The argument from Colorado's point of view must be that they planned a strategy based on the assumption that David Beckham would be in the lineup. The LA Galaxy had two goals before halftime, but we can only speculate as to how much competitive advantage they gained from fudging the injury report.
At the very least, it's unsportsmanlike. But where does it rank in the shady dealings meter? Is it as dastardly as not giving up video footage of your team to your opponent? Or is it as benign as scratching someone hours before the game with tiredness?