Part of what makes a rivalry special is it's not one-sided. Notre Dame currently holds a 45-36-5 lead in the series with USC, which seems fairly even. However, what has been unusual is the extended string of excellence one team has held over the other in cycles:

• In the 27 seasons from 1940-66, Notre Dame held an 18-5-1 lead (no meetings from 1943-45 because of limited travel during World War II) while winning five Associated Press national titles and barely missing in 1948, 1953 and 1964 (although the Irish won a share by getting presented the MacArthur Bowl).

• In the 16 seasons from 1967-82, USC was 12-2-2 against the Irish, capturing or sharing four national titles (1967, 1972, 1974 and 1978). In the two years the Irish did manage to defeat the Men of Troy -1973 and 1977 - they went on to capture the national championship.

• In the 13 seasons from 1983-95, Notre Dame was 12-0-1 against USC, earning the national title in 1988 and barely missing in 1989 and 1993.

• In the 16 seasons from 1996-11, the pendulum swung back in the Trojans' favor with n 12-4 advantage. From 2002-09, USC held an eight-game winning streak against Notre Dame while outscoring the Irish 318-122 - an average of approximately 40-15 per game.

Prior to the 2012 game, Notre Dame head coach Brian Kelly said the series with USC was "not a great rivalry right now" because of the Trojans' 9-1 advantage in the previous 10 meetings that made it too one-sided. The Irish had a 3-1 record against the Trojans under Kelly before last year's 49-14 defeat in which Notre Dame basically fielded its junior varsity defense because of injuries.

"We're past that," said Kelly in 2013 of the one-sidedness. "Now I think it's we would hope that both programs are competing each and every year for BCS Bowls and playoff opportunities, and I think that's where both programs want to be, that they're on equal footing, that you don't have to wait three, four years to get a win. … I think both programs are looking forward to those days where it's a great matchup year in and year out."

The rivalry began in 1926, but it truly heightened in 1964 when both became superpowers again for an extended time and faced each other the next 18 years with at least one, if not both, having the national title on the line.

The 2012 conquest was special, but over the past 50 years, here's one man's ratings of Notre Dame's greatest/most important victories in the series:

5. Nov. 26, 1989: Notre Dame 28, USC 24 — Trailing 17-7 at halftime and its 18-game winning streak in jeopardy, Irish quarterback Tony Rice directs two 80-yard drives in the fourth quarter, scoring the game-winner with 5:18 left. Notre Dame's then makes a late stand inside its 10-yard line to stave off a Trojans team that would go on to win the Rose Bowl.

4. Nov. 26, 1966: Notre Dame 51, USC 0 — Two years earlier, No. 1 Notre Dame with first-year coach Ara Parseghian took a 17-0 lead into the halftime locker room at USC — only to end up losing 20-17. So when the No. 1 Irish hold a 17-0 lead in 1966 with only a couple of minutes left until halftime against the Rose Bowl bound Trojans, Notre Dame linebackers coach John Ray screamed at his crew about the need for another touchdown right before halftime, because it can't be 17-0 again.

Backup sophomore quarterback Coley O'Brien, replacing an injured Terry Hanratty, obliges with a 13-yard scoring toss to classmate Jim Seymour. Not only that, the Notre Dame defense forces a turnover and in the closing seconds O'Brien finds Seymour for a 31-yard score and a 31-0 halftime lead. O'Brien completes 21 of 31 for 255 yards, with Seymour nabbing 11 for 150 yards. The Irish defense also scores twice on interception returns by Tom Schoen and Dave Martin.

3. Oct. 22, 1977: Notre Dame 49, USC 19 — A preseason pick to win the national title, the No. 11 Irish were bumbling along with a 4-1 record while averaging only 20.6 points per game. No. 5 USC was 7-1-2 against the Irish in the last 10 games and had won three straight.

But in one of the best-kept secrets ever at Notre Dame, head coach Dan Devine's Fighting Irish come out in green jerseys — "Dressed to Kill as Sports Illustrated headlined it — after the pregame warm-ups and are transformed into "The Green Machine." Joe Montana rushes for two touchdowns and completes 13 passes for 167 yards, eight of them for 97 yards and two scores to tight end Ken MacAfee. Notre Dame also returns a blocked punt for a touchdown to build a 35-7 lead in the third quarter.

The victory vaults the Irish up to No. 5, and they would average 45.3 points over the final seven games to win the national title.

2. Nov. 26, 1988: Notre Dame 27 USC 10 — The lone game in the series where the teams are ranked No. 1 (Notre Dame) and No. 2 (USC). However, USC is installed as the favorite at home - and the odds increase when Irish head coach Lou Holtz suspends leading rusher Tony Brooks and leading receiver Ricky Watters from the game for repeated tardiness.

The Trojans win the statistical battle (including 21-8 in first downs), but the Irish force key turnovers and use the big scoring plays — a 65-yard run off the option by quarterback Tony Rice and a 64-yard interception return by corner Stan Smagala — to build a 20-7 halftime cushion.

Senior captain Mark Green applies the icing with his second score. Holtz became the fourth Notre Dame head coach to defeat USC handily in his third year en route to the national title. Frank Leahy (26-6 in 1946), Parseghian (51-0 in 1966), Devine (49-19) and Holtz out-score USC 153-35 (an average of 29.5 points) to win national titles.

Kelly won "only" 22-13 in his third year but it concluded a 12-0 regular season with the No. 1 ranking.

1. Oct. 27, 1973: Notre Dame 23, USC 14 — The Trojans had not lost to Notre Dame in seven years, entered the game with a 23-game unbeaten streak and had an aura of invincibility with athletes such as Anthony Davis — six TDs the previous year in a 45-23 win versus the Irish, two of them on kickoff returns — Lynn Swann and dozens of other premier athletes.

The defending national champs lead 7-6 before Irish QB Tom Clements scores on fourth down right before halftime. Then on the first Irish series of the second half, after Notre Dame nearly fumbles the punt, Eric Penick electrifies the audience with an 85-yard scoring run for a 20-7 lead.

USC repeatedly drives deep into Notre Dame territory thereafter, but the Irish force three turnovers to end the drought (in the rain). The student body tears down the goal posts in one of the wildest celebrations ever inside Notre Dame Stadium, and the victory propels Parseghian's second consensus national title.