Although there were two title matches at UFC 187, and it was generally considered the deepest show so far this year, the prelim numbers were slightly below average with 780,000 viewers.
Pay-per-view prelims on FS 1 average about 800,000 viewers, but there is a wide variation. While not a perfect predictor, the shows that do the strongest pay-per-view numbers do the best ratings in most cases. The opposite is also usually the case. So these numbers don't indicate a blockbuster pay-per-view number.
The show was up from the previous month, which did 710,000 viewers for the prelims before UFC 186, the show headlined by Demetrious Johnson vs.