With a first-class physique, unmatched intensity and a ground game that he perfected in UFC, Ken Shamrock debuted in World Wrestling Entertainment in 1997 and was immediately positioned as one of the top babyfaces in the industry.
Shamrock's first major role in the company came as the special guest referee for the iconic Submission match between Steve Austin and Bret Hart at WrestleMania XIII. While he was largely an observer in the match, what he did after the bell by slamming Hart to the mat and preventing him from doing further damage to Austin cemented Bret's heel turn and garnered Shamrock the support of the WWE faithful.
His debut match came at the May 1997 pay-per-view In Your House: A Cold Day In Hell, where he met Vader in a very physical, hard-hitting match.
Despite an onslaught from the massive ring veteran, Shamrock survived and locked in an ankle lock to force a submission victory.
The World's Most Dangerous Man would utilize that ankle lock to become a legitimate contender to any of WWE's championships and a threat to the top stars in the industry. That was never more apparent than at the July '97 In Your House: Canadian Stampede show when he partnered with Steve Austin, the Legion of Doom and Goldust to take on the Hart Foundation.
Shamrock's team would lose that match, but it was the first really great match that the former mixed martial arts star would compete in.
He would spend the remainder of the year mixing it up with "British Bulldog" Davey Boy Smith and feuding with the Nation of Domination, which had recently picked up a new member in the form of Rocky Maivia.
More on him in a moment.
Shamrock's first real test as to whether or not he was a viable main event performer came in December at the D-Generation X pay-per-view when he challenged Shawn Michaels for the WWE Championship.
To say Michaels was less than honorable while guiding Shamrock through the match would be an understatement. The Heartbreak Kid instructed Shamrock to call out his spots in the ring, doing so as loudly as possible. It made the No. 1 contender look like an amateur, and the fact that Michaels himself dogged the match as much as possible only made Shamrock look worse.
He recovered from a poor main event performance to feud with The Rock over the Intercontinental title for the first half of 1998. The rivals would compete against one another at the Royal Rumble in January, at WrestleMania XIV in March and in the finals of the King of the Ring tournament in June.
Shamrock would win that year's tournament, as the company reiterated how much apart of its plans for the future he really was.
A feud with Owen Hart would keep him busy during the summer, leading to the first-ever Lion's Den match at that year's SummerSlam. Unlike any cage match the company had ever seen, it was a fresh concept, and Shamrock and Hart's undeniable chemistry made the match the sleeper hit of the event.
With the proverbial glass ceiling keeping Shamrock firmly entrenched in the midcard, and with no other fresh programs for him to partake in as a hero, Shamrock turned heel and finally put his intensity to good use as he pummeled and punished some of WWE's most popular stars.
Mankind and X-Pac were early targets for Shamrock, as he tore through them en route to capturing the vacant Intercontinental Championship in a one-night tournament held on Raw.
He would hold the title throughout late 1998 and into '99, spending most of that period as a member of Vince McMahon's evil Corporation faction.
Shamrock would also team with Big Boss Man to capture the WWE Tag Team Championships from the New Age Outlaws as he continued to have a very productive span.
Eventually, Shamrock would drop the Intercontinental title to Val Venis at St. Valentine's Day Massacre and the tag titles to Jeff Jarrett and Owen Hart.
A return to babyface status would arrive in May of '99 as he grew tired of Shane McMahon's antics and disrespect of his father and walked out on the Corporation. He would join the short-lived (thankfully) Union faction, partnering with Mankind, Big Show and Test as they waged war with McMahon's followers.
A summertime feud with Steve Blackman was intense and hard-hitting, but the matches between them, including an Iron Circle match and the return of the Lion's Den match, never lived up to their potential.
Unfortunately for Shamrock, repeated injuries kept him out of the ring, and a feud with Chris Jericho was never properly paid off.
Shamrock would never return to WWE programming after heading to the sidelines in the fall of 1999.
In 2002, he joined Jeff Jarrett's upstart NWA: Total Nonstop Action promotion, becoming that company's first heavyweight champion.
Today, Shamrock works private security for some of Hollywood's top stars.
Ken Shamrock is a prime example of a Superstar that seemingly had everything it took to succeed at the very top of professional wrestling but, for whatever reason, never fully reached his potential.
With that said, he did have a very solid career for the three years he was part of WWE and was always a featured player on Monday and Thursday nights. While he never won the world title, he did capture the company's other two major titles and held them for decent lengths of time, cementing his legacy as one of the more successful midcard stars of the Attitude Era.