Jon Jones and Daniel Cormier are fighters, two of the greatest alive. Jones may well be the best who's ever done it.

And so during a news conference open to the public Monday in the lobby of the MGM Grand, Jones and Cormier fought. They didn't get paid, and they're fortunate they didn't lose the opportunity for the big paycheck that will come on Sept. 27 when they meet for Jones' light heavyweight title on the other end of the casino in the Grand Garden Arena.

Injuries happen in these kinds of things – anyone remember Dodgers pitcher Zack Greinke breaking his collarbone last year during a brawl at Dodger Stadium against the Padres? – and the guys who are involved in them usually pay the heaviest price.

Fortunately, neither Jones nor Cormier was seriously injured during the senseless brawl that occurred as they were posing for photographs.

They're going to wind up a bit lighter in the wallet, because the Nevada Athletic Commission will undoubtedly fine them.

More significantly, though, both Jones and Cormier should be thankful that no innocent bystanders got hurt. Then, they really would have problems.

Dave Sholler, the UFC's senior director of public relations, bravely stood between them as it became obvious that the not-so-friendly rivals were about to square off.

Jones leaned forward and put his forehead on Cormier's in what was clearly meant to be a sign of dominance and intimidation.

That was wrong.

Cormier responded by giving Jones a hard two-handed shove.

That was worse.

And then Jones fired a big punch, setting off a wild melee in which they punched and kicked at each other as fans squealed and UFC officials and MGM security guards had to try to break it up.

UFC president Dana White landed in Bora Bora for a short vacation on Monday, so it couldn't have been fun to get the call about the brawl.

But if that's the worst problem that White has to deal with in the rest of his tenure running the UFC, he's a lucky man.

It didn't make either of the participants look good, but that isn't surprising given their childish jabs at each other via social media since the fight was made.

Tensions often are high between the fighters and members of their entourages, because the stakes are enormous.

We can debate forever about whether UFC fighters are paid appropriately or not, but there is no question that the big-name champions like Jones do well.

These fighters are making multi-million dollar paydays, and when that is the case, the stakes are enormous, particularly for guys who are making far, far, far less per fight.

Brawls happen now and again, which is one of the reasons White is always so on edge at weigh-ins. It's his job to keep the fighters from throwing punches at each other as they pose for the traditional staredown photos.

At the weigh-in, the fighters are at their worst. They're dehydrated, they're starved and they're often stressed beyond belief. Given the pressure, it's not unusual that something happens occasionally.

Rarely in the UFC, though, has there been a brawl like what occurred Monday between Jones and Cormier.

It puts a big crimp in the UFC's argument that its fighters are a different breed than boxers. A media person who hasn't heard White or UFC CEO Lorenzo Fertitta talking about how their fighters are college-educated, smarter and more mature than the average boxer hasn't been on the MMA beat very long.

But Jones and Cormier looked anything but like mature, college-educated businessmen.

As a result of their actions Monday, the rest of their public appearances will be filled with tension, and security will be heavy.

It's not the kind of message the UFC wants to send as it tries to push its brand into the mainstream.

Certainly worse happens annually in other sports, and it never seems to impact them much. But there is still a large percentage of people who are put off by MMA and see it as no-holds barred fighting with no rules, which it clearly is not. Many of the people with that attitude view the fighters as blood-thirsty thugs.

That is not true; as a group, MMA fighters are a low-key, easy-going bunch, generally classy and easy to deal with.

But the highlights of this incident, which will be replayed millions of times on television and websites, will unfairly color the perception of the fighters as a whole.

Monday's incident is isolated, and a fine is in order.

In a few days, everyone will move on from the incident, and there will be no long-lasting impact.

But the UFC and other fight promoters should explore ways to take the traditional photos while lessening the risk of an incident occurring.

The fighters don't want to lose a payday. If one of them is injured in a brawl like that, they're not paid. As independent contractors, they're only paid when they step into the cage and the bell rings to begin the bout.

But it's not fair to the fans, either, if a great matchup is torpedoed by a senseless melee like happened in the lobby of the MGM Monday.

Maybe from now on, White or one of his representatives needs to be between the fighters at all times, and not let them pose nose-to-nose.

That will cost a great photo opportunity, but doing that might also prevent a fight-killing brawl, as well.

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