5 UFC fighters who were accused of being unprofessional 

#4. Nick Diaz

As popular as the Diaz brothers are, they have never been treated as centerpieces in the UFC, like a few others. Part of their larger-than-life personas has been fostered by the air of unpredictability the two have displayed throughout their storied careers. While some would simply paint Nick Diaz as anti-establishment, others may interpret his style of doing things as unprofessional.

The infamous Strikeforce brawl in Nashville, Tennessee, comes to mind. After Jake Shields' victory against Dan Henderson, Jason Miller entered the cage unprompted, demanding a rematch. Needless to say, Diaz and his team went on the offensive. In the end, Diaz and Miller were fined and suspended for three months.

After a lengthy lay-off, Nick Diaz returned to action this year against Robbie Lawler. The two first locked horns at UFC 47 in April 2004. Skeptics were concerned the moment the rematch bout was officially announced, but the superstar lived up to his hype, albeit in an unpredictable manner.

While his 'no-show' at a world Jiu-Jitsu expo raised concerns, so did the superstar skipping UFC 266 media day for his fight against Lawler in September. In another display of unprofessionalism, Diaz opted for a 185-pound fight instead of the contracted 170-pound contest. The decision was made in haste, with no specific reason given.

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#3. Jon Jones

Jon Jones is one of the biggest stars of the sport, and his track record of being unprofessional is public and well-documented. Jones is unable to adhere to the UFC's code of conduct policy. Considering his blatant disregard for the consequences of the law, the former UFC light heavyweight champion makes this list.

While some attribute his eye-poking habit to unprofessionalism, that is difficult to prove during a fight. Having been the target of various legal troubles, Jones has often been labeled unprofessional.

Recently, Jon Jones was involved in a widely publicized altercation with his fiancé. While innocent until proven guilty, many are adamant that where there's smoke there's fire.

Jon Jones has also been involved in a litany of failed drug tests. The light heavyweight star was flagged for ingesting banned performance-enhancing substances, and faced penalties from USADA. Jones chalks up many of these infractions to tainted supplements.

Jon Jones' first fight against Alexander Gustafsson was inducted into the UFC Hall of Fame. Just over twelve hours after the elegant ceremony, Jon Jones was arrested for the alleged incident with his fiancé. As one of the most successful MMA fighters of his generation, Jon Jones needs to improve his professionalism.