2 Oregon 70, Colorado 14 updated 5:31 p.m. (AP) - Kenjon Barner rushed for 104 yards and two touchdowns, and No. 2 Oregon easily took care of Colorado 70-14 on Saturday in advance of next weekend's Pac-12 showdown with 10th-ranked USC. De'Anthony Thomas rushed for another score and added a 73-yard punt return for a touchdown before most of the Ducks' offensive starters were pulled midway through the second quarter. Redshirt freshman quarterback Marcus Mariota passed for 136 yards and two TDs. The Ducks (8-0, 5-0 Pac-12) built a 56-0 lead by halftime and their 70 points were the most they'd ever scored against a conference opponent. It was Oregon's 11th straight overall victory dating to a 38-35 loss at home to USC last season. Christian Powell rushed for 127 yards and two touchdowns for the Buffaloes (1-7, 1-4), who lost their fourth straight. The Ducks piled up 617 yards in total offense, including 425 on the ground, and the Buffs simply could not keep up. Colorado went into the game ranked 112th in the nation on defense, allowing an average of 489 yards. Oregon had 447 by halftime. Colorado has yielded at least 50 points in its last three games, including last weekend's 50-6 loss to USC. Oregon scored twice at the start of the game - on Barner's 1-yard run and Thomas' 9-yard run - before Colorado's offense even got the ball. Mariota added a 5-yard scoring run then hit Bralon Addison with a 16-yard TD all before the first quarter ended. Barner added a 24-yard scoring run before Thomas' stunning 73-yard punt return gave Oregon a 42-0 lead. Mariota found Daryle Hawkins with a 7-yard touchdown pass before leaving the game with most of Oregon's other starters. Backup Ducks quarterback Bryan Bennett added a touchdown on a 6-yard keeper before the break and Oregon's 56 points at halftime were its most since scoring 59 on New Mexico in 2010. Powell had a 1-yard scoring run early in the third quarter to avoid the shutout for the Buffs, then added a 20-yard TD dash to narrow it to 56-14. Bennett answered with two keepers, from 3 and 17 years out, to put Oregon up 70-14. Colorado coach Jon Embree started junior quarterback Jordan Webb before putting in sophomore Nick Hirschman. Webb completed seven of 11 passes for 31 yards, while Hirshman finished 7 of 16 for 64 yards. While Oregon remained at No. 2 in the AP Top 25 this week, the Ducks dropped to No. 4 in the BCS standings, which prompted coach Chip Kelly to quip that perhaps the computers were shut down at night before the Ducks played. A victory against USC next weekend would go a long way toward proving that Oregon is worthy of higher standing. The Nov. 3 game at the Coliseum has been touted by many as the most important Pac-12 game of the season - or at least a preview of the conference championship game. Last year the then-No. 18 Trojans came to Autzen Stadium and won, dropping the Ducks from No. 4 to No. 9 in the polls and effectively dashing any hopes at a national title bid. USC is considered Oregon's biggest threat again this season.