Undrafted in 2024, Barnhart joined the Chargers and spent time on the practice squad without a regular-season appearance. He represents a potential swing option at guard or tackle for Pittsburgh if he earns a roster spot.

Karsen Barnhart was released by the Chargers along with Cornelius Johnson and Christopher Hinton. Following their release, Barnhart has since been signed to the Chargers' practice squad.

Karsen Barnhart was waived as part of the Chargers' roster cuts, indicating he did not secure a spot on the final 53-man roster.

Karsen Barnhart, a guard from Michigan, was among the 21 undrafted free agents signed by the Los Angeles Chargers.