With his first-round knockout of Fedor Emelianenko, Dan Henderson has replaced the recently-retired Randy Couture as the most successful 40-year-old fighter competing in the sport today.
As MMA becomes more popular, it will inevitably become increasingly difficult for these older competitors to find success in the sport, but there are currently plenty of elite fighters who haven't seen their 20s in awhile.
At some point, Henderson will retire and the time will come for another fighter to replace him as the living legend of the sport.
Here are the 30 best fighters over the age of 30 competing in MMA today.
At UFC 132, Chris Leben may have ended the career of another aging fighter with his first-round knockout of 35-year-old Wanderlei Silva.
In all his years with the UFC, Leben has never been able to earn a title shot. That may change if "The Crippler" can defeat Mark Munoz in the first five-round non-title fight in UFC history.
Since his loss to Wanderlei Silva in February 2010, Bisping has won three straight fights and earned a spot as coach on Season 14 of TUF.
A win over opposing coach Jason Miller at the series finale could put the Englishman a win or two away from finally competing for the UFC Middleweight Championship.
Brian Stann has revitalized his career with a drop to middleweight, as he has won three straight fights and could be in position to earn a title shot if he wins his next fight.
At UFC 136, Stann willl meet Chael Sonnen in a clash of elite 185-pounders. The winner of that bout would seem to be the most likely choice for top contender in the division.
Prior to his knockout loss against Anderson Silva, Vitor Belfort had accumulated a five-fight winning streak that reached its pinnacle with a first-round knockout of former UFC Middleweight Champion Rich Franklin.
Now, Belfort will look to get back on track with a win over Yoshihiro Akiyama at UFC 133.
There is no doubt Miguel Torres is on the decline. The former WEC Bantamweight Champion has lost three of his last five fights.
However, all of those losses have come against fighters who have fought or will fight for a bantamweight title under Zuffa. Declining or not, Torres is still willing to mix it up with the best in the world.
Although Demian Maia is coming off of a loss, he showed much-improved striking in his last fight against Mark Munoz.
If Maia can show that he has completely rounded out his game in his next fight against Jorge Santiago, there could be time for the Brazilian grappling ace to make one last run at the UFC Middleweight Championship.
With his win over Demian Maia, Mark Munoz has become a serious middleweight contender. As a reward, Munoz will meet Chris Leben in the first five-round non-title fight in UFC history.
In seven middleweight fights, Munoz's only loss has come via split decision against top contender Yushin Okami.
Since leaving the UFC, Fabricio Werdum has gone 3-1 against tough competition. In June 2010, Werdum became the first fighter earn a legitimate defeat of Fedor Emelianenko.
However, Werdum suffered an embarrassing defeat in his last bout, as he refused to engage with Alistair Overeem in the opening round of the Strikeforce Heavyweight Grand Prix.
After a loss to Jake Shields looked as though it could derail the career of Dan Henderson, the former Olympic wrestler captured the Strikeforce Light Heavyweight Championship and then earned a victory over MMA legend Fedor Emelianenko.
With Henderson's Strikeforce contract expired, a return to the UFC and one last shot at a title in the world's premier MMA organization could be up next.
The last time he fought, Alistair Overeem looked less than spectacular in his decision victory over Fabricio Werdum.
At the same time, it is hard to blame Overeem for the performance, as Werdum constantly flopped to his back in an attempt to bait Overeem into a grappling match.
After refusing to compete in the semifinals of the Strikeforce Heavyweight Grand Prix, Overeem was released from the promotion. The MMA world impatiently awaits Overeem's next move.
Frank Mir has regained some steam since his knockout loss to Shane Carwin, as the former UFC Heavyweight Champion has picked up victories over Mirko Filipovic and Roy Nelson.
At the moment, Mir remains without a scheduled opponent. A fight against the winner of a battle between Antonio Rodrigo Nogueira and Brendan Schaub could be a possibility, though.
After losing to UFC Welterweight Champion Georges St-Pierre for the second time in his career, Josh Koscheck is running out of time to capture a UFC title.
Recently, Koscheck has toyed with the idea of moving to middleweight for a fight with Stephan Bonnar.
At this stage in his career, a permanent move to 185 pounds could give Koscheck his best chance at becoming champion.
The most common way for a fighter over the age of 30 to be released from the UFC is to begin declining and losing fights.
However, long-time UFC fighter Nate Marquardt was let go because he essentially ruined the main event of UFC on Versus 4.
Due to increased testosterone levels, Marquardt was not cleared to fight Rick Story just before the two fighters were about to step on the scale at weigh-ins.
Since then, Marquardt has signed with BAMMA. His first opponent in the new promotion has not yet been announced.
In 2010, Brian Bowles lost the WEC Bantamweight Championship and spent the rest of the year healing from injuries.
So far, 2011 has been much more productive for the former champion, as he has picked up two wins already.
In November 2011, Bowles will have a chance to make his year even better, as he will face off against Urijah Faber to determine the top contender in the division.
Few expected Forrest Griffin to rebound completely from back-to-back knockout losses to Rashad Evans and Anderson Silva.
However, Griffin has now picked up back-to-back wins over Tito Ortiz and Rich Franklin.
With a win in his next fight against Mauricio Rua, Griffin could have an argument for a shot at reclaiming the UFC Light Heavyweight Championship.
Shane Carwin has now lost two fights in a row, but he can take something positive away from both of those defeats.
Against Brock Lesnar, Carwin nearly became an undisputed champion with a first-round onslaught. However, Lesnar was able to recover and took advantage of a depleted Carwin in the second round.
In his next fight, Carwin showed improved cardio by going the distance in a loss to Junior dos Santos.
In October 2011, Kenny Florian may get his last shot at fighting for a UFC belt, as he takes on UFC Featherweight Champion Jose Aldo.
Florian has fallen short in two lightweight title fights earlier in his UFC career, losing to Sean Sherk and B.J. Penn.
Despite being dominated by Cain Velasquez, it's hard to argue that Brock Lesnar isn't one of the best heavyweights in the world.
Nonetheless, Lesnar is now battling a second case of diverticulitis and it is hard to tell how much of a toll the illness will take on the former champion's body if he is able to make a return to the Octagon.
In the last five years, Yushin Okami's only losses have come against Rich Franklin, Jake Shields and Chael Sonnen.
Now, the perennially underrated Japanese fighter will get his chance to shock the world, as he is set to take on UFC Middleweight Champion Anderson Silva at UFC 134.
After consecutive losses to Mauricio Rua and Quinton Jackson, rumors began to sprout that Lyoto Machida's job was in jeopardy.
With an incredible knockout of Randy Couture, Machida put an end to that talk, though.
However, Machida recently passed up an opportunity to get back into the title picture when he was asked to replace Phil Davis in a fight against Rashad Evans.
Machida said he would only take the fight for "Anderson Silva money," and the UFC denied his request.
A loss to Rashad Evans and his involvement in acting prompted many to wonder if Quinton Jackson had any desire to fight anymore.
Jackson is now out to dispel that myth, as back-to-back wins have earned the former UFC Light Heavyweight Champion another shot at the belt.
After being dominated by Jose Aldo in a title fight at featherweight, Urijah Faber elected to make a move to the 135-pound division, where he was able to find immediate success.
After two wins, Faber found himself with a title shot and rematch against UFC Bantamweight Champion Dominick Cruz.
Although he ended up losing to Cruz, Faber showed that he can still compete with the best by taking the fight to a narrow decision.
After taking more than a year off due to injuries and waiting for title shots, Rashad Evans is finally set to make his return to the Octagon this weekend.
Although he was previously scheduled to fight Phil Davis, Evans will fight Tito Ortiz in a bout that could determine the top contender in the light heavyweight division.
After losing the UFC Lightweight Championship, B.J. Penn decided to return to welterweight, where he has already marked himself as a contender once again.
In his first 170-pound fight, Penn knocked out former champion Matt Hughes. Then, Penn fought to a narrow decision with Jon Fitch, who is widely regarded as one of the best fighters in the division.
Although he didn't lose to B.J. Penn, Jon Fitch's draw in his last appearance definitely hindered his chances at earning a rematch with UFC Welterweight Champion Georges St-Pierre.
Fitch and Penn were scheduled to fight again, but both fighters were forced out of the bout due to injury. Since Fitch is still recovering, Penn has taken a fight with Carlos Condit.
Jake Shields' loss to Georges St-Pierre was his first in more than six years. Some speculated that Shields could move to middleweight after the loss, but he has decided to remain at welterweight.
Shields will look to rebound against up-and-coming Jake Ellenberger in September 2011.
After legal troubles led to a lengthy suspension, Chael Sonnen is finally set to make his return to the Octagon.
The last time Sonnen made an appearance, he came less than two minutes away from dethroning UFC Middleweight Champion Anderson Silva.
Sonnen will now meet Brian Stann in a fight that could very well determining the next top contender in the middleweight division.
At UFC 125, Gray Maynard came about as close to winning a title as a fighter can get by fighting to a draw with UFC Lightweight Champion.
Maynard nearly finished Edgar in the first round, but Edgar stormed back to retain his belt in dramatic fashion.
Maynard will get another chance at Edgar, as the two are scheduled to meet in October 2011.
In May 2011, UFC Welterweight Champion Georges St-Pierre celebrated his 30th birthday.
One of the most dominant champions in UFC history, St-Pierre will attempt to defend his belt for a seventh consecutive time against Nick Diaz in October 2011.
At 36 years old, Anderson Silva is bound to suffer his first UFC loss at some point. However, I'm not going to bet against him until that day finally comes.
Silva has won 14 straight fights and defended the UFC Middleweight Championship eight consecutive times.
Sean Smith is a Featured Columnist for Bleacher Report MMA. Sean has also had his work featured on UFC.com. For the latest insight and updates on everything MMA, you can follow Sean on Twitter @SeanSmithMMA.