-- It has been a long 21 months since former WWE superstar CM Punk announced his intention to fight in the UFC.
After setting aside nearly a full year to perfect his craft, injuries twice forced Punk to delay his first bout inside the Octagon. Saturday marks go time for the 37-year-old, whose real name is Phil Brooks, in his debut against welterweight Mickey Gall (2-0) at UFC 203 in Cleveland.
From the very first day his signing with the UFC was announced, Punk has had a great attitude regarding what he has gotten himself into, saying, "I felt like it was now or never. I have a limited window most fighters don't have. I'm either here to win or get my ass kicked."
Along the way, as reports began to trickle out from Roufusport in Milwaukee, where he trains, the prevailing theory was that the latter of the two options Punk presented was most likely to happen. Las Vegas oddsmakers agreed, installing Punk as a heavy underdog.
Whether it proves to be sideshow or the beginning of a second career, Punk has retained the respect of many for taking such an unnecessary risk, leaving behind millions of dollars by walking away from his pro wrestling prime. That respect has trickled down to his peers in the world of sports entertainment.
Paul Heyman, who served as Punk's on-screen manager in WWE from 2012 until Punk abruptly walked away from the company in January 2014, has no doubt regarding the intentions of the five-time WWE world champion.
"Any conversation that I had with CM Punk dating back, even when he was still in WWE and was dreaming of getting involved in mixed martial arts, is that he was doing a switchover of careers from becoming a sports entertainer to becoming a full-time, career-oriented mixed martial artist," Heyman told ESPN.com in June.
With Punk currently being sued by a WWE doctor for defamation, it has been difficult for current superstars to speak publicly regarding Punk's UFC debut. But? Seth Rollins, during an August visit to ESPN headquarters in Bristol,?Connecticut, admitted that he's excited to watch the fight.
Rollins also cited Punk as a very influential wrestler who set the stage for WWE's current "new era" of superstars.
"He's a guy who led the charge for a long time," Rollins said. "He's one of the first indie guys in a long, long time to really shake [up] the main roster in WWE and he paved the way for? Daniel Bryan, for myself,? Dean Ambrose,? Cesaro,?and those guys.
"Say what you will about his attitude and his relationship with the company right now, but I wish him the best and I hope that he is successful -- win, lose or draw."
Ryback, who parted ways with WWE on his own terms in August, took offense in recent years to comments made by Punk that he was "reckless" to work with in the ring, which escalated a war of words between them. But Ryback, whose real name is Ryan Reeves, said it has no influence on him wanting to see Punk do well in the UFC.
"From a basic human being standpoint, he is showing courage doing something the majority of people on this planet will never do and that is step in a cage and fight in front of millions of people," Reeves told ESPN.com. "I respect he wants to test himself and has the courage to do so. For that reason alone, while I don't condone him saying the things he said about me, I want to him do well. Any man can beat another man on any given night, so I just hope he achieves what he is looking for in this and I will leave it at that."
Many pro wrestlers have tried their hand at MMA over the years -- and vice versa, to varying degrees of success -- creating a natural crossover between the worlds of scripted fighting and the real thing. No one has been able to make the transition as prominently, and with as much success, as former UFC heavyweight champion Brock Lesnar.
The comparisons between Lesnar and Punk were inevitable, despite the fact that Punk enters MMA as a complete novice, one month shy of his 38th birthday. Lesnar, on the other hand, had a legitimate background as an NCAA Division I champion in wrestling, not to mention that he's simply a freak athlete with natural size and speed advantages over most opponents.
Punk told ESPN Radio in June that Lesnar was excited for him in the beginning, offering his help.
"He said, 'Bug me any time you want, I'll answer all the stupid questions you got,'" Punk said. "And then he gave me some advice. Brock's a nice guy when he wants to be."
But Lesnar, during a visit to Bristol in June to promote his one-off return at UFC 200, downplayed the idea that his ability to float between MMA and WWE was opening doors for others, Punk included.
"There will never be another Brock Lesnar," he said. "You can make all the correlations you want to the people you just stated but none of them have ever main-evented and sold pay-per-views and put asses in the seats like Brock Lesnar. There is nobody."
When it comes to making the adjustment between the two platforms and quickly finding a comfort level, current UFC heavyweight Josh Barnett believes Punk will be just fine. A former pro wrestler himself in Japan, Barnett currently joins WWE Hall of Famer Jim Ross as the voice of New Japan Pro Wrestling on AXS TV.
"I think he has been in the environment long enough and he understands the difference between shooting and working, as we say in the business," Barnett told ESPN.com in January. "The biggest thing for Phil is don't hold back, don't doubt, don't hesitate. Go out there and live your dreams. You're in the UFC, you're here to be an MMA fighter. You put the time in, just go forward. Don't even bother looking behind you and just see what happens."
Despite the UFC heavyweight championship being contested in the main event at UFC 203, as Stipe Miocic makes his first defense against Alistair Overeem, a great deal of the buzz entering Saturday has centered around Punk.
But the question still lingers -- how much does it matter whether Punk is actually competitive, let alone victorious, in terms of justifying his placement on the card as more than just a curiosity to add PPV buys? WWE Hall of Famer Scott Hall believes the UFC has promoted Punk's appearance correctly by allowing his "smirky" personality to show while not misrepresenting what he brings to the table.
"I think people tune in to watch Brock win and I think they are going to tune in to watch Punk lose," Hall told ESPN.com. "I think they employed that strategy in their marketing so if he does anything but get creamed I think he comes out ok. They are not building him up as a big hype or anything.
"They are taking the strategy like let's wait and see. They even showed him training in the cage and all the others guys were kind of standing around yelling at him because it is kind of like, 'Let's see what you got.'"
After a long buildup to get here, Punk will finally get that chance, for better or for worse, on Saturday.