The Longhorns struggled on offense -- as they had throughout an 8-5 season -- but their defense came through with four fumble recoveries and an interception.
Ash put Texas in front at 7-3 in the second quarter by catching a 4-yard pass from wide receiver Jaxson Shipley on a trick play. Ash threw a 47-yard scoring pass to Marquise Goodwin in the third quarter that gave the Longhorns the lead for good at 14-10.
Cody Johnson scored on a 4-yard run on the first play of the fourth quarter, three plays after California quarterback Zach Maynard fumbled the ball away while being sacked at the Texas 44.
Ash completed 14-of-24 passes for 144 yards. The Longhorns picked up 264 total yards to just 187 for the Golden Bears.
The only touchdown for California (7-6) came on a 6-yard run by Isi Sofele in the third quarter that gave the Bears a 10-7 lead.
Texas gave the Big 12 Conference a 2-0 record in bowl games this season. That conference has six bowl games left, including Baylor's meeting with Washington in the Alamo Bowl Thursday.
The Pacific-12 Conference is 0-2 with four games left.
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