They say defense wins championships. Well, creating negative plays typically makes for a winning defense.
We're defining negative plays here as tackles for a loss, sacks, interceptions and forced fumbles (we went with forced fumbles instead of fumble recoveries). We're tallying how many of each that Pac-12 defenses produced in 2013 and -- more importantly -- how many of those negative plays were created by returning players.
We start with the South Division.
(Number in parentheses is number of negative plays made by returning players).
Arizona
Tackles for a loss: 77 (32.5)
Sacks: 24 (11.5)
Interceptions: 18 (12)
Forced fumbles: 9 (6)
Key returners: LB Scooby Wright (9.5 tackles for a loss, 0.5 sacks, 1 interception); S Tra'Mayne Bondurant (7.0 TFL, 2 sacks, 4 INTs, 1 forced fumble)
Key losses: DL Sione Tuihalamaka (11 TFL, 5 sacks, forced fumble); CB Shaquille Richardson (3.0 TFL, 3 INTs)
Breakdown: The Wildcats must replace a lot of production, including their top two tacklers and tackles-for-loss producers. As has been the question for the past few years, it's uncertain who will lead the pass rush.
Arizona State
Tackles for a loss: 101 (16.5)
Sacks: 40 (5)
Interceptions: 21 (4)
Forced fumbles: 14 (6)
Key returners: S Damarious Randall (5.5 tackles for a loss, 3 INTs, 3 forced fumbles); LB Salamo Fiso (5.5 TFL, 3 sacks)
Key losses: DE Carl Bradford (19 TFL, 8.5 sacks, 1 INT, 3 forced fumbles); DB Robert Nelson (6 INTs, forced fumble)
Breakdown: After losing nine starters, including six on the All-Pac-12 first and second teams, the Sun Devils are rebuilding on defense. Considering ASU's system is predicated on negative plays, developing new defensive playmakers is priority No. 1 for the defending South champions.
Colorado
Tackles for a loss: 71 (42.5)
Sacks: 17 (11)
Interceptions: 10 (10)
Forced fumbles: 12 (7)
Key returners: LB Addison Gillam (9.5 tackles for a loss, 3 sacks, INT); CB Greg Henderson (4 interceptions)
Key losses: DE Chidera Uzo-Diribe (10.5 TFL, 4 sacks, 5 forced fumbles)
Breakdown: Other than Uzo-Diribe, just about all the key producers are back. But they need to take a decisive step forward this season. There's a sense in Boulder that the secondary might be ready for prime time.
UCLA
Tackles for a loss: 79 (31)
Sacks: 32 (8)
Interceptions: 14 (11)
Forced fumbles: 17 (9)
Key returners: LB Myles Jack (7.0 tackles for a loss, 1.0 sacks, 2 INTs, forced fumble) CB Ishmael Adams (1.5 tackles for a loss, 0.5 sacks, 4 INTs)
Key losses: OLB Anthony Barr (20 TFL, 10 sacks, 5 forced fumbles); DE Cassius Marsh (9.5 TFL, 6.0 sacks)
Breakdown: Obviously, the loss of Barr is huge, but Marsh and LB Jordan Zumwalt also were highly productive players. The Bruins welcome a lot of guys back but those guys need to step up their negative-play production in 2014 -- paging Myles Jack.
USC
Tackles for a loss: 91 (49)
Sacks: 35 (15)
Interceptions: 17 (11)
Forced fumbles: 8 (6)
Key returners: DE Leonard Williams (13.5 tackles for a loss, 6 sacks, 2 forced fumbles); CB Josh Shaw (5.5 tackles for a loss, 4 INTs)
Key losses: OLB Devon Kennard (13 TFL, 9.0 sacks); DB Dion Bailey (6.5 TFL, 0.5 sacks, 5 INTs, forced fumble)
Breakdown: USC welcomes back its three leading tacklers. Replacing Kennard's production is the big question for the defense. It was a huge gain for the Trojans when Shaw opted to return, as he solidified what should be a good secondary.
Utah
Tackles for a loss: 80 (31.5)
Sacks: 39 (13.5)
Interceptions: 3 (0)
Forced fumbles: 13 (7)
Key returner: DE Nate Orchard (9 tackles for a loss, 3.5 sacks, 3 forced fumbles)
Key losses: OLB Trevor Reilly (16 TFL, 8.5 sacks, 1 INT, 1 forced fumble); LB Jacoby Hale (10 TFL, 6.5 sacks)
Breakdown: Reilly was, by far, the Utes' best and most productive defensive player, but the loss of Hale to a serious knee injury this spring also hurts. It's pretty astounding that the Utes don't have a player coming back who had an interception in 2013.