Phillips, a 9-year veteran who came to the Broncos this season from San Diego, scooped up a fumble by receiver A.J. Jenkins and brought it back for the score. It was a disappointing night for Jenkins, who in his second year with the 49ers had been expected to make an impact this season.
Peyton Manning played briefly for the Broncos and completed 2-of-4 passes for 13 yards. Brock Osweiler went 13-of-18 for 105 yards without an interception.
The only San Francisco points came on field goals of 32 and 38 yards by Phil Dawson.
2014: NFL Cheerleaders [PHOTOS]
Julius Randle breaks leg during NBA debut