NAPA, Calif. -- Miami Dolphins defensive end Chop Robinson will not play Sunday against the San Francisco 49ers after suffering a concussion during Wednesday's practice, coach Jeff Hafley said.
Robinson remains in the concussion protocol and will miss at least this week's game.
After playing their season opener in Las Vegas, the Dolphins opted to remain out West and have practiced in Napa this week in preparation for Sunday's game.
Robinson was listed as a limited participant on Wednesday's injury report and was seen Thursday walking around the practice field with a team trainer.
Without Robinson, the Dolphins will rely on veterans Josh Uche, Clelin Ferrell, Rob Beal Jr. and Malik Herring to pressure 49ers quarterback Brock Purdy. Hafley said.
"It's all of the above. We might do some other things to help out," Hafley said. "But I have confidence in those guys. ... They've done a good job at practice this week, and it'll be the next man up."
Robinson, who was tabbed as a breakout candidate coming into the season, has 10 sacks since the Dolphins selected him 21st overall in the 2024 draft. He was a standout performer throughout training camp and recorded a team-high three pressures during Miami's loss to the Las Vegas Raiders in Week 1.
This is the third documented concussion of Robinson's NFL career. He sustained two during the 2025 season, missing two games as a result.
"Chop is a great young player who I think is going to be great in his league, so it hurts not to have him," linebacker Jordyn Brooks said.
Sunday's matchup could prove challenging for a Dolphins defense that registered a 33.3% pass rush win rate in Week 1, the third-lowest rate in the league. In contrast, San Francisco won 64.7% of its pass block attempts in its win over the Los Angeles Rams last week, which ranked fourth.
The Dolphins failed to sack Raiders quarterback Kirk Cousins in Week 1, despite Cousins recording the 19th-fastest average time to throw in the NFL last week.
Defensive coordinator Sean Duggan said there's more to impacting opposing quarterbacks than sacks, but he wants to see his unit build on an improved second half, when Miami held the Raiders to 3.3 yards per play and forced two turnovers.
"I felt like we kind of tiptoed a little bit, especially early in the game," Duggan said. "I think they got comfortable as the game went on and our play got better. What I really want to see is guys go play confident, cut it loose a little bit, but within the realm of our defense and within having great fundamentals.
"... I think affecting the quarterback is more than just stats. It's closing the pocket, it's affecting throws, which I think we did, particularly in the second half. So I really just want to see us continue to build on that."