UFC on FOX 20 wasn't exactly a card stacked with names, particularly after the original co-main event of Anthony Johnson vs. Glover Teixeira was postponed, but Holly Holm's first UFC main event as an A-side headliner proved to be a huge one for FOX ratings.
Overnight numbers came in at 2.4 million viewers, which was the highest for a big FOX event since Anthony Johnson's KO of Alexander Gustafsson in January 2015. The final numbers, adjusting for West Coast viewing figures and running past the two-hour timeslot, topped out at 2.975 million viewers (via MMA Fighting), which comes in just below the 3.049 million mark for Rumble vs. Gustafsson.
The standout number from this event is easily the peak viewership. Rounds 3-5 of the main event between Holly Holm and Valentina Shevchenko averaged just under 4.7 million viewers, which is the highest peak number since the 4.977 million who tuned in for Ben Henderson's win over Gilbert Melendez in April 2013. The first 3 fights on the main card ranged from 2.1-2.9 million viewers, with rounds 1-2 of Holm vs. Shevchenko averaging 3.8 million. So while the card as a whole wasn't a massive show, the decision to have Holm vs. Shevchenko as the main event paid off in a big way. It should be pointed out that the UFC's biggest FOX cards have generally had the backing of heavy advertisement on NFL broadcasts, so this event was the highest rated one for any summer FOX card, and the headliner outperformed several fights that had the benefit of the NFL push.
There's no doubt that Holm's profile was raised considerably with her KO win over Ronda Rousey, and she still managed great ratings even following her dramatic loss to Miesha Tate at UFC 196. How she'll fare going forward after that performance against Shevchenko remains to be seen, but there's no denying that she proved she could be a main event draw on her own.
For other UFC on FOX 20 tidbits, the prelims averaged 1.261 million viewers on FOX, with the post-fight show on FS1 clocking in at 222,000 viewers.