Who will play in Las Vegas Bowl? SDSU? BYU? UCLA? Who knows

We're six days from the announcement of the second College Football Playoffs and the bowl assignments, but we're no closer to knowing who will play in the Royal Purple Las Vegas Bowl.

The opponents for the Dec. 19 game at Sam Boyd Stadium is at the mercy of BYU, the Mountain West Championship Game and the whim of the Pac-12.

First, the Mountain West title game is set for Saturday in San Diego, where Air Force (6-2 league) meets San Diego State (8-0). Most bookmakers have made the Aztecs as a 5½-point favorite, especially since it is on their home field.

But the Mountain West winner is not a stone-cold, lead-pipe lock for the Las Vegas Bowl. BYU is in the mix as part of a prior arrangement to have its choice of the Las Vegas Bowl or the Aloha Bowl if the Cougars reach nine wins, which they did Saturday.

Cougars players said Saturday they would rather come to Las Vegas. BYU boosters are pushing for a Hawaii trip because the men's basketball game is playing in a Honolulu tournament the same week as the bowl game.

"I think the wish is that it's in Las Vegas because it's closer to here, we'll have more fans there and it will feel like a bigger game," wide receiver Mitch Mathews told the Deseret News. "The last time we were there we beat Oregon State (2009). We like to play there. I think that's where the guys are most excited about, going there."

And the Las Vegas Bowl opponent is set to be the No. 6 team in the Pac-12, but that could be UCLA, Cal or Washington State, depending upon who is doing the math. Plus, the Pac-12 might decide not to send UCLA back to Las Vegas because the Bruins already have played a September game at Sam Body against host UNLV.

That's why we really won't know who's playing here until 5 p.m. Sunday as the playoff participants and the bowl opponents are announced.

Until then, here's the latest projections the Las Vegas Bowl from various media outlets:

* ESPN's Mark Schlabach and Brett McMurphy: San Diego State vs. Washington State.

* CBS Sports' Jerry Palm: San Diego State vs. Washington State.

* SB Nation: BYU vs. Cal.

* Sports Illustrated: BYU vs. Cal.

* Sporting News: Washington State vs. Air Force.

* Fox Sports: San Diego State vs. UCLA.

In other words, we still don't know who's playing at Sam Boyd Stadium in 19 days.

This we do know: BYU would fill the house, UCLA already half-filled the stadium in September and we have no recent track record of how well Washington State and San Diego State fans travel.

Bill Bradley is Sports Editor of the Review-Journal. He can be reached at 702-387-2909 or at bbradley@reviewjournal.com. Follow on Twitter: @billbradleylv