Tamina was attempting to hit a Samoan drop, only for Bayley to counter into a crucifix pin.
The titleholder took advantage of Sasha Banks distracting her opponent and held Tamina's shoulders down for the three-count to retain the championship.
The issues between Bayley and Tamina dated back to before WrestleMania 36, which is where the former managed to retain the SmackDown women's title against four other women, including Tamina, in an elimination match.
Tamina correctly pointed out it took all four other Superstars in the match to work together in order to pin her, which led to her asking for a title shot. The champion agreed to give her one but only if she could beat Banks to earn it.
On a recent episode of SmackDown, Tamina defeated The Legit Boss after Lacey Evans ran down to prevent Bayley from distracting Tamina and interfering in the match.
The rivalry between Bayley and Tamina continued to grow from that point forward. After Evans beat Banks in a Money in the Bank qualifying match because of botched interference from the titleholder, Tamina laid out Bayley with a superkick at the top of the stage.
The following week on SmackDown, The Legit Boss tricked Tamina into getting jumped by Bayley backstage, but Evans got involved and prevented the heel duo from inflicting too much damage.
Although Tamina has been on WWE's main roster since 2010, her title opportunities have been few and far between. In fact, she hadn't been part of a televised one-on-one match for a singles women's championship since Extreme Rules 2014 before Sunday.
Meanwhile, Bayley entered Money in the Bank with tons of momentum. She won the SmackDown Women's Championship at last year's Money in the Bank, dropped it to Charlotte Flair 140 days later and then won it back less than a week later.
That meant The Role Model had held the SmackDown women's title for nearly one year straight entering Sunday's PPV. She also beat many capable challengers during that reign, including Charlotte, Evans, Carmella, Naomi, Nikki Cross, Alexa Bliss and Ember Moon.
Given the storylines surrounding both competitors, including the recent problems between Bayley and Banks, there was no shortage of intrigue surrounding Sunday's title match.
Bayley left with her title reign intact as expected, which means the door remains open for her and Banks to branch off and feud over the SmackDown Women's Championship at some point in the near future.
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