Austin Roberts hit the fields at Hoag Performance Center earlier this month as a non-contract participant at rookie minicamp.
He parlayed his performance into a spot on the 90-man roster.
The Chargers announced Wednesday that they signed the UCLA product, adding another tight end to the mix. To make room, the team waived long snapper Anthony Kukwa.
Roberts is a 6-2, 230-pound tight end known for his pass-catching prowess. He appeared in 10 games with three starts a year ago for the Bruins, catching 19 passes for 220 yards and two touchdowns. Overall, he played in 24 career games over three seasons at UCLA, totaling 35 receptions for 500 yards and three TDs.