By the time the College Football Playoff selection committee unveils its first rankings of the season Oct. 31, it’ll be able to weigh some compelling additional evidence.

It’ll know how Penn State, ranked No. 2 in this week’s Associated Press and coaches’ polls, measured in telling  games against Michigan (Saturday) and Ohio State (Oct. 28).

It’ll know how Georgia, ranked No. 3 in this week’s polls, fared in its annual test against Florida in Jacksonville (Oct. 28).

And it’ll be able to factor another two weekends worth of potential upsets into the equation.

The road to the playoff – and ultimately to the national championship game in Atlanta – took unexpected turns last week with four top-10 teams losing, three of them to double-digit underdogs.

Clemson’s loss to Syracuse cleared the way for Penn State and Georgia to move up one spot each in the AP poll, behind unanimous No. 1 Alabama. TCU rose from No. 6 to No. 4, benefiting from the losses by Clemson and Washington.

(Caveat: The AP and coaches’ polls ultimately will have no bearing on determining the four-team playoff field. But until the 13-member selection committee starts ranking teams on Halloween, the other polls provide a reference point.)

The first losses of the season by Clemson and Washington, who fell from Nos. 2 and 5 to Nos. 7 and 12 in the AP poll, respectively, hardly removed those teams from playoff contention. Remember that the national champion in each of the first three years of the playoff had one loss.

But last week’s losses did cost the Tigers and Huskies their margins for error. Remember that no two-loss team has reached the playoff.

Both Clemson and Washington are off this week before facing Georgia Tech and UCLA, respectively, on Oct. 28. The selection committee will watch to see how they bounce back.

Here's the rest of our weekly update on the College Football Playoff's road to Atlanta: 

ALABAMA AND/OR GEORGIA? 

If both Alabama and Georgia -- two of the six remaining unbeaten power-conference teams -- keep winning until they collide in the SEC Championship game, the question will grow larger and louder: Could both teams make the playoff?

In the CFP’s first three years, no more than one team from a single conference  reached the playoff in any given season.

But USA Today, CBS Sports and Sports Illustrated all projected this week that both the Crimson Tide and the Bulldogs will reach this season’s playoff.

USA Today projected semifinals of Alabama vs. TCU in the Sugar Bowl and Georgia vs. Penn State in the Rose Bowl, with Alabama then meeting Penn State for the national title at Mercedes-Benz Stadium on Jan. 8. 

Four members of CBS Sports’ seven-person midseason panel and five members of Sports Illustrated’s seven-person panel picked both Alabama and Georgia to reach the playoff.

If two teams from one conference reach the playoff, that would mean at least two of the five power conferences would be shut out.

THIS WEEK’S KEY GAMES 

Here are two games on this weekend’s slate with apparent playoff implications:

No. 2 Penn State (6-0) at home vs. No. 19 Michigan (5-1), 7:30 p.m. Saturday, ABC: The Nittany Lions have won 14 consecutive regular-season games and 15 of 16 games overall since losing 49-10 in Week 4 of last season to … Michigan. Although Penn State running back and Heisman Trophy candidate Saquon Barkley leads FBS in all-purpose yards with 217 per game, the game could be dominated by defense: Penn State leads FBS teams in scoring defense, allowing just 9.0 points per game, and Michigan leads in total defense, yielding 223.8 yards per game. If Penn State wins, its game at Ohio State a week later becomes even bigger.

No. 11 USC (6-1) at No. 13 Notre Dame (5-1), 7:30 p.m. Saturday, NBC: The winner will remain in the playoff picture. The loser will slide out of the picture. This game marks the first time since 2009 that these storied rivals have met with both ranked. USC currently is the highest-ranked Pac-12 team, and Notre Dame's 1-point loss to Georgia looks better now that the Bulldogs are 7-0.

ASKED AND ANSWERED

Q: Who has the better team, No. 1 Alabama or No. 3 Georgia?

A: "Alabama is the better team, just to my mind, having played both and having seen where they're at," Vanderbilt coach Derek Mason, whose Commodores lost to Alabama 59-0 and to Georgia 45-14, answered on the SEC coaches' weekly conference call with the media Wednesday. "I think they both have potent offenses. They both have really good running backs. Alabama's receivers are probably a little more experienced in terms of playing big games. Both (defensive) fronts are extremely good. But I think the difference is in Alabama's secondary.

“It's a potent secondary that has got corners and safeties that are lock-down guys. You’re probably going to have four of those guys back there seeing NFL rosters at some point in time. I think that’s what makes the difference, not just the ability of your corners to lock down, but the ability of your safeties to cover sideline to sideline and in the box and really show range of deep defense. Alabama is just a truly dominant defense right now.”

ROAD TO ATLANTA

Oct. 31: College Football Playoff selection committee releases its first rankings of the season

Dec. 3: "Selection Sunday," when the committee's final rankings set the four-team playoff bracket

Jan. 1: Playoff semifinals in the Rose and Sugar bowls

Jan. 8: National championship game at Mercedes-Benz Stadium