SALT LAKE CITY -- It took surviving a sloppy game, but Utah clinched a share of its first Pac-12 South title.

Running back Joe Williams rushed for 187 yards and a touchdown on 34 carries to help the No. 23 Utes overcome turnovers and pull away for a 20-14 victory over Colorado on Saturday.

The Utes and Buffaloes combined for seven turnovers. Utah (9-3, 6-3 Pac-12) was able to offset its mistakes with strong defensive play. The Utes had six sacks and stopped Colorado in the red zone on consecutive first-quarter drives.

It helped Utah finish in a first-place tie with USC in the Pac-12 South. The Buffaloes (4-9, 1-8 Pac-12) last beat the Utes in Salt Lake City in 2011.

"They deserve to go out on a winning note in the regular season," Utah coach Kyle Whittingham said of his team. "Co-champs of the South. That's a great accomplishment for our seniors."

Colorado did everything it could to complicate that finish.

The Buffaloes marched down to the Utah 8-yard line on their opening drive but came away empty-handed when defensive end Kylie Fitts blocked a 31-yard field goal attempt by kicker Diego Gonzalez.

Utah made the big special teams play count. The Utes quickly marched down the field on their initial drive, and quarterback Travis Wilson finished off the drive with a 16-yard pass to receiver Kenneth Scott for a 7-0 advantage.

Colorado pushed into the red zone again on its second drive after a 50-yard pass from quarterback Cade Apsay to Spruce set up the Buffaloes at the Utah 27. Once again, the Buffaloes couldn't finish the drive as Utes Safety Marcus Williams hauled in a tipped ball at the 14 to keep Colorado off the board.

"We all thought we had a good red zone package going into this week," Spruce said. "They gave us the looks we expected. We just really didn't execute."

Utah extended its lead to 10-0 on a 37-yard field goal from Andy Phillips with 7:27 remaining in the second quarter.

Colorado finally got back into the game when Boobie Hobbs fumbled on a punt return. The Buffaloes took over at the Utah 33 and cut the Utes' lead to 10-7 when Apsay hit Spruce on a crossing route for a 28-yard score.

Utah had a chance to add to its lead just before halftime. The Utes drove down to the Colorado 15 following a 64-yard run from Williams. But Wilson threw into triple coverage and safety Tedric Thompson picked off his pass in the end zone to stop the drive.

Utah finally increased its lead to 17-7 after Williams burst up the middle for a 5-yard touchdown run early in the third quarter. Then linebacker Gionni Paul picked off a pass from Jordan Gehrke at the Utah 28, setting up a 27-yard field goal from Phillips to make it 20-7.

"We didn't move the ball there for a little while," Buffaloes coach Mike MacIntyre said. "Had some opportunities to (score). Just didn't make some plays. It bogged us down a little bit."

Colorado made things interesting late in the fourth quarter. Wide receiver Phillip Lindsay scored on a 16-yard pass from Gehrke with 4:13 left, cutting Utah's lead to 20-14.

After forcing a punt, the Buffaloes drove to the Utah 47 in the final minute. Jared Norris recovered a fumble by Gehrke on a sack to end the drive and preserve a Ute win.

Now Utah is heading back to a bowl game for the second straight season and the Utes have their first 10-win season as a Pac-12 member finally within reach.

"We still have one more game, and it is our job as a whole Utah team to win bowl games," Wilson said. "We've just got to make sure we are prepared. Whatever we draw, we've got to be prepared for it."

NOTES: Utah beat Colorado for the fourth consecutive season. The Utes last won four straight over the Buffaloes during a nine-game winning streak in the series from 1925 to 1933. ... WR Nelson Spruce set a Colorado record with his 23rd career touchdown reception. Spruce already had career marks for receptions and receiving yards. He finished with 111 yards and a touchdown on five receptions. ... DT Viliseni Fauonuku had four sacks for Utah. Those were his first sacks of the season.