AJ Styles has had one hell of a career. The Phenomenal One has killed it everywhere he's been and has rightfully become a legend in both TNA and WWE for his work in the two promotions, but his two-year stint in New Japan Pro Wrestling is actually the best run of his entire career.

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Having spent over a decade with TNA, Styles decided it was time to seek pastures new in 2014, and many weren't sure whether it was the right move to make. After all, he'd become synonymous with the promotion, and it was yet to be seen whether he could replicate his success there somewhere else.

Those doubts were soon squashed though and the former TNA champion ventured over to Japan, becoming an instant success. He immediately became one of the biggest names in all of New Japan, shooting straight into the main event scene and joining the hugely popular Bullet Club faction.

His run in New Japan was a brief, but an incredibly memorable one, and looking at the body of work he produced in such a short amount of time, it certainly may be the best period in his entire wrestling career.

He Wrestled In Some Sensational Matches

While it was evident for all to see just how good a wrestler AJ was in TNA, and his body of work in the company was very impressive, he truly took it up a notch once he arrived in New Japan.

From his very first match against Kazuchika Okada at Wrestling Dontaku 2014, Styles was in sublime form and didn't disappoint whenever he stepped in-between the ropes. He churned out five-star matches with absolutely anyone put in front of him, and he really solidified his place amongst the very best wrestlers in the world.

AJ Styles Kazuchika Okada

Throughout his two-year run in Japan, the Phenomenal One put on clinics with the likes of Hiroshi Tanahashi, Minoru Sizuki, Kota Ibushi, and Tetsuya Naito. His crowning glory, though, was his final match in the promotion. Just days before he departed for WWE, AJ had probably the best match of his career when he fought Shinsuke Nakamura at Wrestle Kingdom 10.

The bout earned acclaim worldwide and was the main reason fans were clamoring to see the two face off at Wrestlemania 34.

He Ran The Bullet Club

New Japan issued a major statement of intent with just how well they planned to use Styles when he aligned himself with the Bullet Club immediately into his run with the promotion.

The stable was the most popular in the world, and with leader Prince Devitt having recently left for WWE, Styles was chosen as his successor. He was a perfect fit for the role as well, and his time with the group elevated both himself and the entire faction.

Styles' time with Bullet Club really helped to take the group to the next level, and they were arguably at their most popular when he was at the helm. Over the years since, Bullet Club has seen its popularity begin to flounder, while WWE's numerous attempts at recapturing the magic of Styles' time in the group under their own umbrella have often fallen flat, and it serves as a stark reminder that this was when he was truly at his best.

He Was The First American IWGP Heavyweight Champion Since Brock Lesnar

Upon Styles' debut in New Japan, he immediately targeted the IWGP Heavyweight champion Okada, and it set the tone for his run in the promotion right out of the gate. In fact, his very first match in the promotion saw him win the title, becoming only the sixth non-Japanese in the company's history to do so.

AJ Styles IWGP Championship

The now 44-year-old was the first American champion since Brock Lesnar in 2005, a true reflection on just how impressive the feat was. Styles would win the championship twice during his time in New Japan and successfully defended it against the likes of Ibushi and Okada along the way.

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Despite failing to achieve any other major accolades during his run in New Japan, Styles still felt like the absolute biggest star in professional wrestling by the time he decided to leave for WWE. He'd really taken his star power to another level after leaving TNA, and it's reasonable to suggest that without his run in Japan, his eventual arrival in WWE at Royal Rumble 2016 wouldn't have been as special.

Sure, after six years in Vince McMahon's promotion, Styles is as big a star now as he has ever been, but he is yet to replicate the incredible body of work he put together in New Japan.