[Dwain] Chambers also faces a backlash from sponsors. Adidas has contacted UKA to stress that the kit which the sprinter wore in the indoor trials in Sheffield on Sunday was not a newly supplied one and that it wishes to distance itself from him.(emphasis added)
You may also be aware that Chambers is effectively banned from all major European invitationals. If meets don't want you and sponsors don't want you, you can no longer be considered a "professional", and if this becomes standard then athletes who choose to dope don't risk a mere 2-year ban but rather their entire livelihood.
I have no illusions that this took place because the moneymakers discovered ethics. Rather, it's because there has been such a huge outcry in the UK over the whole affair. The lesson to learn, then, is to complain long and loud about dopers why try to come back.
UPDATE: Apparently you can't get a manager, either.