Everett Golson scored on a quarterback sneak in the third overtime to end it.
Notre Dame (9-0) is off to its best start since 1993. Pitt (4-5) missed a potential game-winning field goal in overtime.
The Fighting Irish were among four unbeaten teams atop the BCS standings coming into the weekend. Notre Dame was supposed to have the easiest game of the three.
No. 2 Oregon stayed undefeated with a wild 62-51 victory at No. 18 Southern California.
No. 1 Alabama came from behind with a late touchdown to beat No. 5 LSU 21-17 in Death Valley, and No. 3 Kansas State beat Oklahoma State 44-30.
No. 1 ALABAMA 21, No. 5 LSU 17
BATON ROUGE, La. (AP) — A.J. McCarron read an LSU blitz and flipped a swing pass to T.J. Yeldon, who did the rest on a 28-yard touchdown with 51 seconds remaining that gave the Crimson Tide a victory.
Alabama (9-0, 6-0 Southeastern Conference) now has a clear path to the league championship game in Atlanta, and remains solidly on course to defend its national title in Miami.
But this one was a struggle. Led by embattled quarterback Zach Mettenberger, LSU (7-2, 3-2) fought back from a 14-3 halftime deficit with an offensive performance that was nothing like their dismal showing against the Tide in last season's BCS championship game.
Mettenberger hooked up with Jarvis Landry on a 14-yard touchdown that put the Tigers ahead 17-14 with just under 13 minutes remaining.
No. 2 OREGON 62, No. 18 USC 51
LOS ANGELES (AP) — Kenjon Barner rushed for a school-record 321 yards and five touchdowns, Marcus Mariota threw four TD passes, and Oregon produced another landmark offensive performance against USC.
Josh Huff caught two touchdowns, and De'Anthony Thomas and Daryl Hawkins also caught scoring passes for the Ducks (9-0, 6-0 Pac-12), who outlasted USC in a back-and-forth second half to extend their winning streak to 12 games.
Oregon's 730 yards and 62 points were the most ever allowed by USC, which began playing football in 1888.
Barner set a rushing record for a USC opponent by the third quarter, topping Curtis Enis' 241 yards for Penn State in 1996, and smashed the school record shortly afterward as the Ducks gradually pulled away in their closest game of the year.
Matt Barkley passed for 484 yards and four touchdowns while hitting Marqise Lee with 12 passes for 157 yards and two touchdowns for the Trojans (6-3, 3-3), who have lost two straight after a 6-1 start.
No. 3 KANSAS STATE 44, OKLAHOMA STATE 30
MANHATTAN, Kan. (AP) — Collin Klein piled up more than 300 yards of offense before leaving in the third quarter with an undisclosed injury, and Kansas State remained unbeaten.
Klein had thrown for 245 yards and run for 64 more before sneaking in for his 50th career rushing touchdown with 9:47 left in the third quarter. The Heisman Trophy front-runner didn't return to the field on the Wildcats' next offensive series.
By that point, the Wildcats (9-0, 6-0 Big 12) simply had to protect a 38-17 lead.
Oklahoma State's Wes Lunt also left with an injury after throwing his third interception in the third quarter. The freshman quarterback, who missed six weeks with a knee injury earlier this year, threw for 184 yards and a touchdown before giving way to Clint Chelf.
Chelf finished 16 of 27 for 233 yards and a touchdown for the Cowboys (5-3, 3-2.
No. 4 NOTRE DAME 29, PITTSBURGH 26
SOUTH BEND, Ind. (AP) — Everett Golson scored on a quarterback sneak in the third overtime and threw two touchdown pass during Notre Dame's fourth-quarter comeback.
Notre Dame (9-0) won despite Ray Graham rushing for 172 yards for Pitt (4-5), which missed a potential game-winning field goal in overtime.
Golson threw an 11-yard touchdown pass early in the fourth. Notre Dame's chances for a comeback appeared to end when Pitt's K'Waun Williams intercepted Golson in the end zone.
But the Irish defense held and Golson completed a 45-yard pass to DaVaris Daniels at the Pitt 5. Golson then threw a 5-yard TD pass and ran in the two-point conversion to tie the game.
No. 6 OHIO ST. 52, ILLINOIS 22
COLUMBUS, Ohio (AP) — Carlos Hyde rushed for 137 yards and three touchdowns, and Braxton Miller passed for two scores and ran for another to lead Ohio State past Illinois.
The Buckeyes (10-0, 6-0 Big Ten) maintained the upper hand in the Leaders Division heading into a bye week. They have games remaining at Wisconsin on Nov. 17 and against rival Michigan at home a week later.
Miller, considered a Heisman Trophy hopeful, had 18 carries for 73 yards and completed 12 of 20 passes for 226 yards.
It was the sixth straight loss for Illinois (2-7, 0-5) and its 11th Big Ten loss in a row.
No. 7 GEORGIA 37, MISSISSIPPI 10
ATHENS, Ga. (AP) — Aaron Murray threw four touchdown passes and Georgia overcame a slow start to beat Mississippi and move one win away from a spot in the SEC championship game.
Georgia (8-1, 6-1) trailed 10-0 before scoring 37 unanswered points. The Bulldogs can clinch the SEC East title and second straight trip to the conference championship game with a win at Auburn next week.
Ole Miss (5-4, 2-3) used blitzes to record five sacks in the first half. The defensive gambles left opportunities for Murray, who completed 21 of 28 passes for 384 yards with no interceptions and touchdown passes of 66, 40, 42 and 28 yards.
No. 8 FLORIDA 14, MISSOURI 7
GAINESVILLE, Fla. (AP) — Mike Gillislee took a screen pass and went 45 yards for a touchdown, and Florida survived a scare to beat Southeastern Conference newcomer Missouri.
The Gators kept alive their hopes of winning the SEC's Eastern Division.
Florida (8-1, 7-1) was shut out in the first half, managing just 111 yards and failing to contain Missouri quarterback James Franklin. The Gators played considerably better in the second half, turning two short fields into touchdowns, with Omarius Hines scoring on a 36-yard jet sweep to tie the game in the third before Gillislee put Florida ahead for good in the fourth.
Franklin finished with four interceptions for the Tigers (4-5, 1-5).
No. 10 CLEMSON 56, DUKE 20
DURHAM, N.C. (AP) — Tajh Boyd threw for 344 yards and tied a school record with five touchdown passes for the second straight week for Clemson.
DeAndre Hopkins caught three of those TD tosses in the opening quarter for the Tigers (8-1, 5-1 Atlantic Coast Conference), who scored 42 points by halftime and rolled to their fifth straight win — all by at least 14 points. Sammy Watkins and Martavis Bryant also had first-half touchdown catches, helping Clemson rack up nearly 500 yards by halftime and 718 for the game.
The win moved Clemson into a tie with No. 9 Florida State atop the ACC's Atlantic Division, though the Seminoles beat the Tigers in September for the head-to-head tiebreaker in the division race to reach the ACC championship game.
The loss dropped Duke (6-4, 3-3) a game behind Miami for the Coastal Division lead.
No. 12 LOUISVILLE 45, TEMPLE 17
LOUISVILLE, Ky. (AP) — Teddy Bridgewater threw a career-high five touchdowns and Louisville rallied again to beat Temple.
The Cardinals (9-0, 4-0 Big East) fell behind for the sixth straight game, but Louisville scored on five of its first six possessions to take a 31-17 halftime lead. The Cardinals, off to their best start in school history, moved into a first-place tie with Rutgers.
Temple (3-5, 2-3) lost its third straight, getting outscored 127-44 during that stretch.
Bridgewater completed 19 of 28 passes for 324 yards, a week after he threw for a career-best 416 yards against Cincinnati.