Per the NFL's official transaction log, the Chargers have been granted a roster exemption for Gordon in advance of Sunday's game against the Dolphins.
Following a lengthy contract-related holdout, Gordon reported to the Chargers' facility Thursday and promptly rejoined practice. While the team is not expected to activate Gordon this weekend, he's a candidate to be worked back into the team's backfield in Week 5's home game against the Broncos. Austin Ekeler is thus presumably in line for one more start Sunday, with Justin Jackson on hand to work in a complementary role.