Cain Velasquez vs Junior dos Santos staredown pic from UFC 166 media day in Houston, Texas

These two are probably tired of staring at each other by now.

To be fair, this is the third time Cain Velasquez will fight Junior dos Santos with the Ultimate Fighting Championship (UFC) heavyweight title on the line. They first did the deed back at UFC on FOX 1 in late 2011, then evened the score at UFC 155 last December.

UFC 166 marks their long-awaited rubber match.

If you factor in all the press conferences -- one to announce the event as well as the one right before the show -- then throw in two different weigh-in staredowns to accompany any and all media appearances (like this one), that leaves you with over 10 documented face offs.

And we've captured them all.

That includes today's main event mean mugging, which took place in "The Lone Star State" in advance of the upcoming UFC 166: "Velasquez vs. Dos Santos 3" pay-per-view (PPV) event, which comes to a head this Saturday night (Oct. 19, 2013) at the Toyota Center in Houston, Texas.

Check it out (via Andrew Hemingway/MMA Fighting):

In the co-main, Roy Nelson will try to send Daniel Cormier to his first professional mixed martial arts (MMA) defeat, while simultaneously spoiling "DC's" plans to demand a title shot at 205 pounds. The best part of their photo op is the fact that Cormier had to get up close and personal with the same beard he tried to 86 earlier in the week.

And, of course, let's not leave out the Lightweight showdown between Gilbert Melendez and Diego Sanchez, who is unsurprisingly already fired up to punch the former Strikeforce champion.

MMAmania.com will provide LIVE round-by-round, blow-by-blow coverage of the entire UFC 166 event on fight night, starting with the Facebook "Prelims," which are scheduled to begin at 6 p.m. ET, right on through the FOX Sports 1-televised under card bouts at 8 p.m. ET and then main card PPV action, which is slated to begin at 10 p.m. ET.

To see the entire UFC 166 fight card click here. News, notes and other items of interest can be found in our "Velasquez vs. Dos Santos 3" news archive here.