1. Ayaka Hamasaki (14-2)Though she has enjoyed a distinguished career as a strawweight, Hamasaki would surely love to forget her return to 115 pounds, as the Invicta atomweight champion was torn apart by Brazilian Livia Renata Souza in 101 seconds in March. What better way to forget such a loss than to go back and defend the crown of the division you rule? Unfortunately for the 35-year-old Japanese fighter, her next title defense still figures to come against Jinh Yu Frey, who was soundly besting Hamasaki in their September 2016 Invicta title fight until the ringside physician halted the challenger on a cut.
2. Jinh Yu Frey (6-2)Frey has been on the receiving end of some raw deals through little fault of her own. She was beating up Invicta titleholder and pound-for-pound entrant Ayaka Hamasaki in September 2016 -- until she was stopped on a cut. Six months later, she saw her fight with then-undefeated Janaisa Morandin fall apart due to the Brazilian’s botched weight cut. Nonetheless, Frey picked up a unanimous decision over Ashley Cummins in July and now has the chance to make Christmas come early. The half-Korean will head to Seoul to challenge Seo Hee Ham for Road Fighting Championship’s title on Dec. 23 in a massive atomweight clash.
3. Herica Tiburcio (11-4)It was nearly two years ago that Ayaka Hamasaki upset Tiburcio to take the Invicta atomweight title. It was over 14 months ago that Tiburcio came back to the Invicta cage, only to be upset by Jinh Yu Frey. Now, the 25-year-old Brazilian has put together back-to-back decision wins over Simona Soukupova and fellow ranker Tessa Simpson and may not be far off from another crack at Invicta's 105-pound strap.
4. Seo Hee Ham (18-8)Between facing women a division above her natural weight class and some iffy decisions, Ham deserved better than the 1-3 record she put together under UFC employ. However, the minute “Hamderlei Silva” left the promotion and cut back down to atomweight in her native South Korea, she looked rejuvenated, hammering Japan’s Mina Kurobe to win the Road Fighting Championship title in June. Her first title defense will come in an awesome pairing, as Ham stakes her throne against former Invicta title challenger Jinh Yu Frey at Road Fighting Championship 45 on Dec. 23 in Seoul.
5. Mina Kurobe (10-3)Kurobe had been on a hot streak prior to her showdown with Seo Hee Ham, picking up wins over Tomo Maesawa, Saori Ishioka and Naho Sugiyama. However, the 40-year-old fighter's roll slowed considerably at Road Fighting Championship 39 in South Korea on June 10 in her first fight ever outside of Japan, as “Hamderlei Silva” beat her down for 14 minutes before notching the third-round knockout.
6. Naho Sugiyama (12-5)Sugiyama topped Emi Tomimatsu in June to become Deep Jewels atomweight champion. Unfortunately, in her first title defense on Feb. 25, she could not replicate her November 2015 win over Mina Kurobe, dropping a unanimous decision and the strap.
7. Tessa Simpson (5-2)Since finishing college and returning to MMA, Simpson has been sterling, taking quality wins over Satomi Takano and Simona Soukupova. At Invicta 23, the Guam native took a jump up in competition, faced former promotional atomweight champion Herica Tiburcio and pushed the Brazilian to the limit. However, Simpson ultimately wound up losing a split decision on the scorecards after 15 minutes.
8. Maria Oliveira Mota (10-2)Talk about a breakout performance. Few knew of Mota prior to her appearance in Rizin Fighting Federation’s grand prix, but after spending most of her career at 115 pounds, “Neta” dropped back to atomweight and completely dominated Alyssa Garcia for 15 minutes. The 20-year-old is a product of Parana Vale Tudo, the home of Invicta champ Jennifer Maia and top UFC contender Jessica Andrade; and she might be another in the recent line of PVT stars if she can clinch Rizin’s tournament later this year.
9. Kanna Asakura (9-2)Having just turned 20 years old and with barely two years of pro MMA experience under her belt, Asakura is learning on the job. Make no mistake, though: the Paraestra Matsudo product is a quick study. Since her loss to American Alyssa Garcia in December, Asakura has gone 4-0 in 2017, showing increasing competence each time out. With her Oct. 15 win over Poland’s Sylvia Juskiewicz, Asakura punched her ticket to the semifinals of Rizin’s atomweight grand prix and could close out the calendar year 6-0 and ranked among the best in the division.
10. Rena Kubota (5-0)Kubota has been the female face of Shoot Boxing since 2009, but we are just now getting to see her actual MMA potential. At Rizin’s women's atomweight grand prix kickoff on Oct. 15 in Fukuoka, Japan, Kubota moved to 5-0 -- all five of her wins have resulted in stoppages -- with the biggest win of her young career, destroying former King of the Cage atomweight champ Andy Nguyen with a savage liver shot. Will she end 2017 with a Rizin title to go with her four Shoot Boxing S-Cup championships? Time will tell.
Other Contenders: Ashley Cummins, Julia Jones, Sheila Padilla, Satomi Takano, Emi Tomimatsu.