It was the best of times, it was the worst of times. Wait. That's been used before. But, with apologies to Dickens, it fits. The Pac-12 weekend was a tale of one division, two teams, two cities, two quarterbacks, and it was a day of thrills and it was a day of misery.

The plot certainly thickened in the Pac-12's South Division on Saturday, but not necessarily in a good way.

A week after posting a gritty upset at Stanford, USC was humiliated at Boston College, while UCLA cobbled together a win over Texas behind scrappy, ebullient backup QB Jerry Neuheisel. Neuheisel's services were required because Heisman Trophy candidate Brett Hundley was knocked out of the game in the first quarter with an elbow injury. His status remains uncertain, though there was reasonable hope based on initial reports that his injury wasn't serious.

USC's shocking loss to Boston College underscored the vulnerability within the Pac-12 South division. Winslow Townson/Getty Images

Our second city is Tempe, Arizona, where UCLA will be on Thursday, Sept. 25, squaring off with defending South Division champion Arizona State, which beat Colorado on Saturday but also lost its star senior quarterback, Taylor Kelly, who beat out Hundley for second-team All-Pac-12 last year. Seeing Kelly on crutches due to a foot injury -- and his body language -- probably won't fuel great expectations that he will be ready for the Bruins.

The UCLA-Arizona State game was one we eyeballed in the preseason as a major measuring stick in the battle for the South. A significant part of the appeal was the quarterback battle. That hasn't changed, only now the intrigue is whether it will be Neuheisel for UCLA and Mike Bercovici for Arizona State. A week ago, that quarterback news would have heavily favored the Sun Devils. While Bercovici isn't the runner Kelly is, he's got one of the best arms in the conference and is well-versed in the Sun Devils offense. He is expected to win the starting job as a fifth-year senior next fall. Neuheisel was widely viewed as a career backup with a well-known father -- former UCLA QB and coach Rick Neuheisel -- but his second-half performance against the Longhorns suggested he can be more than a rudimentary game manager.

Both teams have an off week, when they can either get healthy or retool their plans. The stakes continue to be high, perhaps more so after USC threw up on itself with a wet-noodle performance at Boston College. While a nonconference game doesn't affect the Trojans' Pac-12 standing, it certainly made them look extremely vulnerable heading into a much-needed bye week. Other than USC fans, the most miserable folks watching that game surely root for Stanford, which probably can't believe it lost to the Trojans just a week before.

What this implosion and these injuries reveal in a wider sense is vulnerability in the South. In the preseason, UCLA looked like a decisive South favorite. Then USC made a statement with a win over the Cardinal. Arizona State was lurking with a great offense and a questionable defense. At this point, however, none of these three teams is scaring anyone. And don't look now, but Arizona and Utah remain unbeaten and have shown flashes that suggest they might be factors in a divisional race that previously seemed limited to the aforementioned troika.

The Wildcats play host to California on Saturday. Lo and behold, the Bears also are unbeaten, and this game suddenly possesses some potential meaning it didn't seem to have in the preseason. If Cal gets the upset, it can fully erase last season's misery and start thinking bowl game. If Arizona gets the win, it will be 4-0 and eyeballing the Top 25 with a visit to No. 2 Oregon looming on Thursday, Oct. 2.

Arizona appears suspect on defense, but the offense, with impressive redshirt freshman QB Anu Solomon, a good O-line, deep corps of receivers and breakout freshman running back Nick Wilson, will make the Wildcats a threat to any foe.

Utah visits Michigan on Saturday. While the Wolverines don't look like they'll be hailing in much victory this season, a Utes win would certainly raise more than a few eyebrows. While Utah's trouble hasn't been in nonconference games since joining the Pac-12, a 3-0 start would hint they are not a South afterthought, particularly if the offense continues to shine with QB Travis Wilson.

While Oregon's win over Michigan State coupled with Stanford's loss to USC only boosted the Ducks' status as North Division favorites, the South intrigue has seemingly spiderwebbed since the beginning of the season. The race appears more wide open and complicated. UCLA's visit to Arizona State remains a major measuring stick, but it's just as likely either team would sacrifice that game -- as horrible as that sounds -- to know it will get its starting quarterback back healthy for the rest of the season.