Video: Preview of tonight's 'UFC 166 Primetime: Velasquez vs. dos Santos' debut

The first of the three-part “UFC Primetime: Velasquez vs. dos Santos III” series premieres tonight on FOX Sports 1, and a short video preview is now available.

The acclaimed series previews the upcoming UFC 166 headliner and trilogy fight between heavyweight champion Cain Velasquez (12-1 MMA, 10-1 UFC) and former titleholder Junior dos Santos (16-2 MMA, 10-1 UFC).

Tonight’s Part 1 debut airs at 8:30 p.m. ET (5:30 p.m. PT). Replays air throughout the week on FOX Sports 2, as well as FOX Sports Net regional cable networks.

UFC 166 takes place Oct. 19 at Toyota Center in Houston. The main card airs on pay-per-view following prelims on FOX Sports 1 and Facebook.

The final two episodes of the three-part series debut next week (Oct. 9) and the week of the fight (Oct. 16).

The UFC most recently aired a “Primetime” special for February’s UFC 157 event, which saw UFC women’s bantamweight champion Ronda Rousey submit Liz Carmouche with a first-round armbar. It marked the first women’s fight (and headliner) in UFC history.

For the latest on UFC 166, stay tuned to the UFC Rumors section of the site.