With rare exceptions, the more dominant the champion, the more destructive their downfall. While they are on the top of the mountain, defeating all on-comers, there is always a challenger watching and honing their skills to be the perfect foil.

The classic case in point is Holly Holm. Already an accomplished boxer – boxing archive BoxRec has her listed as the best female boxer of all time – Holm fleshed out her game with both kickboxing and grappling defense. When she faced then-UFC women's bantamweight champion Ronda Rousey at UFC 193 in Melbourne, Australia on November 15, 2015, she was the perfect foil.

Her second-round headkick knockout victory ended the Rousey era and became an immediate highlight that trended around the globe. But with her greatest foe defeated, that left Holm looking for a new identity as a fighter. From a perfect record of 10-0 to 12-5, Holm found herself losing to fighters she wasn't suited for, such as submission specialist Miesha Tate and the significantly larger women of the featherweight division, which was essentially created so that 65.2 -kilogram Cris Cyborg had somewhere to fight.

However, at 38-years-old, it seems the American fighter nicknamed "The Preacher's Daughter" is having something of an Indian summer as she beat Raquel Pennington with a one-sided decision at UFC 246 earlier this year in Las Vegas, Nevada, and she put on a clinic against #5 bantamweight Irene Aldana of Mexico in the first female main event at UFC Fight Island.

From the very start of Round 1, Holm controlled the Octagon. For the first half of the round, she walked Aldana down and then, toward the end, circled around Aldana clockwise. This kept her at Aldana's southpaw side, preventing her from throwing anything more serious than jabs. In the final minute, Holm switched it up completely from her usual boxing and kickboxing style and attempted a takedown, which Aldana defended up to the final few seconds.

Aldana was more active in Round 2 but found herself on the receiving end of counter combinations and Holm's favorite, the sidekick to the body. This chipped away at Aldana's defense. But in Round 3, Holm's fast combos were either followed by or feinted into hard hooks and high head kicks.

Any time it seemed as if Aldana was figuring Holm out, she threw in a takedown. Each time it was a struggle, and it's difficult to tell how good Holm is at grappling as, according to UFCstats.com, Aldana has the best takedown defense off all the female fighters in the UFC, yet she still managed to repeatedly drag her to the floor with body locks and do damage on the ground.

Before Round 4, Aldana's cornermen were honest with their fighter: she had lost three rounds and now needed a finish to win. Having spent a whole standard fight playing defense, she entered the main event rounds aggressively. It backfired as Holm's specialty in her MMA and boxing career is countering. She backed off, forcing Aldana to chase, and then, when she got close, Holm immediately forced her away with long front and side kicks, and the occasional straight punch.

Holm's nose was bleeding going into the final round, a reflection of Aldana's power, but it came from one punch in an exchange at the end of Round 4; otherwise, it was complete dominance, and that continued for the final five minutes. Aldana tried to bullrush Holm at points only to find herself going headfirst into Holm's varied and powerful strikes. In the final 40 seconds, triggered by a stunning head kick to a staggered Aldana, Holm appeared to be looking for the finish and hit her rival with everything she had.

Aldana survived, and it went to the judges. As expected, Holly Holm won a unanimous decision (50-44, 50-45 and 50-45). This fight wasn't simply commanding; this was the best Holm has ever been – even better than as champion. Holm said post-fight that she didn't want to be a boxer in the MMA cage, she wanted to be a mixed martial artist, and all the new additions to her fight style – the takedowns, the level changes, the constant movement, the aggression – show that at almost 40 years of age, she's still learning and most definitely a championship contender.