Earlier I put up a post that summarized the offensive performance of the teams that reached the BCS title game and talked about the need for a balanced offense in today's competitive college football environment. The tail end of the post included some points of reference comparing the 2006 USC offense to the average performance of the teams that reached the BCS title game in 2000-2006. Interestingly the average rush offense and pass offense rank for these teams that reached the BCS game was only around 30th in the NCAA. Very few teams with Top 10 offenses reached the title game. The big exception was 2005 when Texas and USC reached the title game.
In addition I thought it might be insightful to compare the 2006 USC Trojan's defense along a couple of simple categories to recent BCS participants as well. For simplicity I took the initial set of data points for defense from the NCAA's statistical web site for each BCS team from 2000-2006. I included USC and Michigan for 2003 as well due to the controversy of that year and the split national championship. The data points were rush defense rank, rush yards allowed, pass defense rank, pass yards allowed, total defense rank, total defense yards allowed, scoring defense rank, scoring defense points allowed, and turnover margin rank.
(Note: other defensive stats are perhaps more useful (Sacks, TFL's 3rd down defensive efficiency, and others etc.) however they are not available for each team going back in time to 2000 on the NCAA website. For reasons of simplicity I defaulted to what is available as of right now. In future years more meaningful comparisons can be generated. Also none of this is adjusted of course for strength of schedule, blow out wins, or the shorter game in 2006 due to the clock rule changes. It is only intended as a directional comparison for the sake of simple reference).
For starters let's look at a histogram for the rush defense rank of the teams that reached the BCS title game in this decade. Right off the bat you can see that seven of the 16 teams were ranked in the Top 10 (FSU 2000, OSU 2002, LSU 2003, USC 2003, USC 2004, Oklahoma 2004, and Florida 2006) in this regard. Two more were in the Top 20 (OSU 2006, Oklahoma 2003). Stopping the run is a key component for any defense as it puts the opposition in 2nd or 3rd and long situations where the offense is forced to pass. There is only one abnormal data point in the period in question and that is the 2002 Miami Hurricanes rush defense. That squad allowed 165.3 yards per game and only ranked 72nd in the country that year. Their pass defense was ranked #1 in nation however as we will see below. Still the Hurricanes lost the title game that year to Ohio State. Maybe a balanced defense is necessary as well as a balanced offense?
How does the 2006 USC squad hold up in terms of rush defense? Overall USC ranked 9th in the nation allowing only 97.1 yards per game on average. This level is probably good enough to help reach the title game in 2007 but will no doubt improve. In 2003 and 2004 the USC squad ranked #1 in the nation in rush defense. With improvement and good luck in avoiding the injury bug the 2007 squad might reach that lofty level once again.
Next below here is the histogram for the pass defense ranking and yardage allowed. With pass defense there is more variation in ranking than the rush defense ranking above. On reason is probably the pass happy nature of some conferences. USC has not ranked highly in this regard and that partially explains the data below. Six of the sixteen teams were in the Top 10 in Pass Defense (Oklahoma 2000, Miami 2001, Nebraska 2001, Miami 2002, Oklahoma 2003, and Texas 2005). The Miami secondaries were indeed good and put numerous players into the NFL draft. Other teams from the Big 12 however come from conferences that on average are not as adept at passing (Texas Tech and a few others excluded of course). USC's rankings on pass defense by contrast were 110th in 2003, 34th in 2004, and 73rd in 2005. The type of offensive play in the Pac 10 no doubt has some influence on those numbers as well.
How did the 2006 USC Trojans stack up? In 2006 the Trojans ranked 64th in pass defense in the country allowing 204.8 yards per game. This figure is roughly in line with USC teams of the past and stands to improve in 2007. With a highly experienced secondary returning this season I expect this number to improve and perhaps be as strong as any USC unit in recent memory.
In terms of total defense we see a combination of the two charts from above in terms of ranking and yardage allowed. Ten of the teams in the survey were in the Top 10 in defense the year they reached the championship game. It is shorter to list who was not in the Top 10 (OSU in 2002, USC in 2003, Oklahoma in 2004, and USC in 2005). Of those teams only the 2003 Trojans managed to win their respective championship game and technically no BCS game team has done it in the survey as USC beat Michigan in the Rose Bowl. I read somewhere that had the 2005 Trojans won the title they would have had the worst defensive ranking of any team in history of the NCAA to do so...and still some people blame the offense that year!
How do the 2006 USC Trojans compare. On average the USC squad was 20th and allowed 295.8 yards per game. This puts them near the level they need to perform historically to reach the title game. The squad did benefit from a shorter game in 2006 however so the figure is artificially low on the yardage side. Still however this figures to be a USC strength in 2007 and might match the squads from 2003 and 2004.
Next is the histogram for scoring defense rank and points allowed by the defense. Here again you can see that there are seven teams that ranked in the Top 5 and four more that ranked in the Top 10 for a total of eleven teams. This edges out Total Yards Allowed as the stat that most likely indicated success in reaching the BCS title game in this small survey. The seven teams that ranked in the Top 5 were FSU in 2000, Miami in 2001, OSU in 2002, LSU in 2003, Oklahoma in 2003, USC in 2004, and OSU in 2005. The 2005 USC squad is the team way out to the right in the histogram. That squad allowed 22.8 points per game and of course gave up 41 to Texas in the title game.
How does the 2006 squad look in comparison. The Trojans ranked 11th in 2006 in scoring defense and allowed 15.2 points per game. This performance is in line with previous teams that reached the bowl game. However it still leaves room for improvement and I expect USC to be in the Top 5 in this category when the season is finished in 2007.
The final NCAA rank that I will mention is that of Turnover Margin since it is a Pete Carroll favorite. Five teams that reached the BCS game have ranked in the Top 10 in this metric between 2000 and 2006. Those five teams were Miami in 2001, Oklahoma in 2003, and USC in 2003, 2004, and 2005. On average teams making the BCS game have only ranked 25th in the nation.
How did the 2006 squad perform? The Trojans ranked 38th in the nation in terms of turnover margin and this was the lowest ranking of the Pete Carroll era. It is not far off of the average performance of other teams. However given that USC does not hang its hat on special teams play it needs to shine on turnovers. In 2003 for example USC forced 42 turnovers to lead the nation. In contrast in 2006 USC only forced 22. That is a difference of 20 extra drives per game for the offense. Since the average game only has about 12-14 drives that is equivalent to over one and half games of extra drives for the offense in 2003. Similar numbers were also recorded in 2004 and even 2005. Returning to the Top 10 in this metric will be one of the key points for USC in 2007.
For simplicity here is a table summarizing the performance of the BCS participants and the BCS winner versus the 2006 USC Trojans. In general the 2006 defense stacks up fairly well with these other teams in recent historical perspective. Pass defense, total defense, and turnover margin need to all improve at the margin by a few points of performance. I'm confident that under Pete Carroll and staff the 2007 unit should improve further and help enable the Trojans to return to the BCS game in January of 2008.
So there you have it. In general from a recent historical NCAA statistical data point of view the Trojans are not far off the mark from where they need to perform to reach the BCS title game. Factor in the returning personnel and USC should crack the Top 10 in numerous defensive categories in 2007. Unlike the offensive side of the ball where an NCAA ranking in the range of 30th is sufficient to make it to the title game on defense it requires a Top 10 performance in multiple categories. Perhaps there is truth to the old coaching statement that offense is nice but defense still wins championships.