Bradley Wiggins says he "can't fathom" how Lizzie Armitstead came to miss three doping tests in less than a year.
World road race champion Armitstead was only able to compete at the Rio Olympics after successfully appealing to the Court of Arbitration for Sport (CAS) against a suspension imposed by UK Anti-Doping (UKAD).
The first of Armitstead's three infractions, in August 2015, was struck off the record on account of a testing official being at fault, with the 27-year-old accusing UKAD of "not following proper procedure".
Armitstead. who has a clear blood passport and revealed she had been tested 16 times in 2016 ahead of the Olympics, blamed a "filing failure" and "incredibly difficult" family circumstances for her subsequent strikes.
Yet five-time Olympic gold medallist and former Tour de France champion Wiggins told the Guardian's Weekend magazine there was "no excuse" for missing three tests.
"It's bloody hard because what happens is you miss one test, they write you a letter, they ask you to explain what happened and you've got two weeks to put a case forward. If you ignore that and then you get another one, you end up having crisis meetings," said Wiggins.
"You get a lot of support from UK Sport. They're brilliant, actually. They're on the phone daily. They send you emails, reminders, they'll put plans in place for you in terms of someone helping you with the whereabouts, so you don't end up... well, it's very difficult, then, to go from two to three [missed tests]. And to get three within eight or nine months, there's no excuse.
"When you're a professional athlete and you're a world champion, there's no excuse, because it's your career. You're setting the standard for everybody else, and to say, 'Cycling wasn't my priority at that time' is ludicrous, because you nearly lost your career over it. That's just ridiculous. So I can't fathom how that happened."
Armitstead went on to finish fifth in the women's road race at Rio 2016, having claimed a silver medal in the same event at London 2012.