Aaron Donald’s comeback has hit its first real speed bump.

The Los Angeles Rams defensive tackle will not play Sunday against the Philadelphia Eagles at Lincoln Financial Field after back soreness kept the 35-year-old out of practice throughout the week.

Rams’ head coach Sean McVay made the announcement on Friday before the team’s final preparations ahead of their flight to Philadelphia.

Donald missed Wednesday and Thursday before failing to get back onto the field Friday, leaving the Rams without their future Hall of Fame defensive lineman for a difficult road assignment in Philadelphia.

For Donald, the timing is especially frustrating. He is only two games into his return from a retirement that kept him away from NFL football for more than 2½ years, and just as his body was beginning to adjust to the punishment of Sundays again, it delivered another reminder of how unforgiving that process can be.

Donald first appeared on the Rams’ Week 4 injury report Wednesday with back soreness and did not participate in practice. He remained sidelined Thursday, making Friday’s final practice the critical checkpoint for his availability against the Eagles.

Friday normally serves as Donald’s veteran rest day, but this week was different. After missing the previous two practices because of an actual injury rather than scheduled maintenance, his status became one of the biggest questions surrounding the Rams.

Rams’ tight-end Terrance Ferguson and cornerback Jaylen Watson will also be out for Sunday, per McVay.

The Rams have been deliberate with Donald’s workload since his stunning return to the NFL, understanding there is no substitute for football conditioning after such a lengthy absence.

Donald returned to action against the New York Giants after missing the Rams’ season opener against the San Francisco 49ers in Australia, then played again last week in Denver.

Download The California Post App, follow us on social, and subscribe to our newsletters