Los Angeles Chargers strong safety Adrian Phillips broke his forearm Sunday during a loss at the Detroit Lions, and he's expected to be sidelined indefinitely, a league source told ESPN's Adam Schefter.
Phillips was replacing injured standout safety Derwin James, who sustained a stress fracture in his right foot that required surgery during training camp last month.
Jaylen Watkins is listed behind Phillips on the Chargers' depth chart. He made one tackle in each of the first two games.
James said Thursday the team plans for him to return this season once he's healthy. The Chargers placed James on injured reserve to start the season, which means he must miss at least the first eight games of the year.