A physical altercation occurred during the 49ers training session on Friday. The incident involved Dre Greenlaw and Christian McCaffrey, with the two players getting into a shoving match along the sidelines. Details of the altercation are limited, but it is reported to have been a minor incident.

The source of the tension between Greenlaw and McCaffrey is not specified in the available information. For further details on the incident, including the context and any potential consequences, readers can refer to the original report from The San Francisco Standard.