Kelley took two carries for 78 yards and a touchdown in Friday's 23-12 preseason win over the 49ers.
Kelley started and played the first two drives, taking his second carry 75 yards for a touchdown. Isaiah Spiller and the team's trio of undrafted rookie RBs were all less impressive, making Kelley a comfortable favorite for the No. 2 role behind Austin Ekeler when the Chargers host the Dolphins in Week 1.