What goes up must come down. Right? In the world of mixed martial arts, that is the way it goes. Eventually, every major player in the sport finds out how bitter defeat can taste.
In 2012, several fighters made major leaps and bounds for their careers. Unfortunately, not everyone who was on the ascent has been able to continue climbing the ladder in the new year.
Here is a look at 10 MMA studs from 2012 who have taken a step back in 2013.
Michael McDonald only competed once during 2012, however, in that contest, the youngster made major waves by knocking out former WEC champion Miguel Torres in violent fashion. Widely viewed as the best contender for bantamweight gold, McDonald got his opportunity in early 2013.
"Mayday" suffered his first loss since early 2009, when he was choked out by interim champion Renan Barao at UFC on Fuel 7.
In a best-case scenario following a loss, McDonald would have gotten back on the horse and taken a fight to get himself back into the win column. However, nearly three months later, the 22-year-old still doesn't have his next matchup booked.
In 2012, Donald "Cowboy" Cerrone put together a pair of impressive wins in the lightweight division. After dominating Jeremy Stephens from bell to bell, the former WEC standout picked up a Knockout of the Night and Fight of the Night bonus for his 76-second dispatching of Melvin Guillard at UFC 150.
At UFC on Fox 6, Cerrone met Anthony Pettis in an important divisional matchup. A win could have placed Cowboy next in line for a crack at the belt, but we will never find out for sure.
Cerrone was violently knocked out by Pettis halfway through the first round, which drops him from title discussions. The popular stud will meet K.J. Noons at UFC 160.
Francis Carmont went 3-0 inside the Octagon during 2012, and that winning streak continued in 2013 when he picked up a unanimous-decision victory against Lorenz Larkin at UFC on Fox 7.
So why does the French fighter find himself on a list of combatants who took a step back in 2013? Because the judges who gave him his April victory unanimously made a bonehead decision that only two of 11 critics agreed with, according to MMADecisions.com.
This was the second consecutive victory of Carmont that was deemed controversial, as a November win against Tom Lawlor came in similar fashion.
Whether or not Carmont's win streak is intact, fans no longer seem to view the Tristar Gym member as a player in the middleweight division after stealing back-to-back decisions.
From the end of 2009 until kicking off 2013, Matt Wiman held a 5-1 record in the UFC lightweight division, with his sole loss coming via a razor-thin decision to Dennis Siver. In 2012, the TUF alumnus surprised many when he tapped out submission master Paul Sass.
Wiman looked to parlay his momentum in January at UFC on Fox 6 by taking on T.J. Grant. Unfortunately, "Handsome" was unable to handle the clinch striking from Grant and was knocked out with elbows in the first round.
Although Andrew Craig is hardly a household name, in 2012, the undefeated middleweight snuck onto the radar by upsetting Kyle Noke and Rafael Natal in his first UFC appearances.
In January, Craig competed against Ronny Markes in Brazil at UFC on FX 7. At that event, his undefeated record took on its first blemish when he lost a unanimous decision.
In 2012, Siyar Bahadurzada made his UFC debut in spectacular fashion when he knocked out tough-as-nails Paulo Thiago in only 42 seconds. The win was the seventh in a row for the Afghanistan native and made him one of the hottest prospects to watch at welterweight.
The shine on Bahadurzada was quickly removed in 2013 after he was outgrappled and outclassed by judo master Dong Hyun Kim in Japan. Two months after the matchup, he doesn't have another fight on the books.
Olympian Daniel Cormier sits undefeated with a flawless 12-0 record, and in 2012, the AKA member won the Strikeforce heavyweight Grand Prix by dominating former UFC champion Josh Barnett in exciting fashion.
2013 has been kind to Cormier, as the wrestler picked up a win on the final Strikeforce card as well as a win over Frank Mir in his UFC debut.
So why is he on our list?
Cormier may have shut out Mir back in April, but he hardly impressed anyone with his method of attack. All three rounds saw the Strikeforce stud hold Mir against the cage and stall for time between body punches. Continually through the bout, referee Herb Dean restarted the fighters in the center of the Octagon due to lack of action.
This sleepy performance was addressed by Cormier, who told MMAjunkie.com that he was displeased with his fight.
... But man, I was nervous. I felt so nervous. It's almost like you want it so bad and you want to do so well, and then you just kind of lay an egg a little bit. I didn't fight the fight I wanted to.
Cormier's standing in the rankings has improved, but by putting on such a boring showing in the co-main event of a card that aired on national television, he hurt his marketability in a major way.
Darren Elkins kicked off his featherweight career with five consecutive victories, and two of those wins came in 2012. The wrestler became a serious name to watch throughout the year when he dominated Ultimate Fighter winner Diego Brandao and surging fighter Steven Siler.
Elkins actually found success in 2013 when he knocked out Antonio Carvalho at UFC 158, but "The Damage" quickly found out that he wasn't ready for the big leagues at UFC on Fox 7 when he was quickly and viciously knocked out by one-time contender Chad Mendes.
Although Elkins showed his bravery by stepping up for a major fight on short notice, nothing kills momentum like a 68-second knockout loss.
2012 was a comeback year for one-time UFC contender Nate Marquardt. The longtime middleweight made a successful drop to 170 pounds when he knocked out Tyron Woodley for the vacant Strikeforce welterweight championship.
When 2013 kicked off, Marquardt was widely expected to defeat challenger Tarec Saffiedine on the final card in Strikeforce history, but he was unprepared for the heavy assault of leg kicks that were thrown in his direction.
Not only did Marquardt drop a decision loss to Saffiedine and lose his belt, "The Great" was violently knocked out by Jake Ellenberger in his return to the UFC at UFC 158.
Three appearances. Three wins. Three stoppages.
That's the kind of success achieved by UFC heavyweight Stefan Struve during 2012. "The Skyscraper" handed Stipe Miocic, Lavar Johnson and Dave Herman their first losses inside the Octagon.
However, that momentum came to a screeching halt in March when the big man took on "Super Samoan" Mark Hunt.
Despite being able to work the fight to the floor on several occasions, Struve was unable to parlay his incredible grappling advantage into a submission victory. Hunt repeatedly got back to his feet and eventually scored a third-round stoppage when he broke Struve's jaw with a leaping hook.