The San Francisco 49ers are preparing for their Week 2 contest against the Detroit Lions on Sunday at Levi's Stadium.

The 49ers placed linebacker Brock Coyle on injured reserve on Wednesday and revealed that he suffered a T4 compression fracture (broken bone in his back) against the Minnesota Vikings.

"We've got (Joshua) Garnett, (Mike) Person, (Marquise) Goodwin, and Malcolm (Smith) today, they're all in the same boat," head coach Kyle Shanahan said. "None of them are going to practice. They'll all be questionable for the game. (Erik) Magnuson is the only guy who didn't play last week, who we'll try him out in [individual drills] today."

Starting safety Adrian Colbert did not practice on Wednesday while safety Jaquiski Tartt and cornerback K'Waun Williams were in blue no-contact jerseys. Colbert reportedly has a tight hamstring. He was seen doing conditional work on a side field.

Below are Wednesday's practice participation reports for both the 49ers and Lions, which were provided by the 49ers Communications staff.

San Francisco 49ers Wednesday Practice

Did Not Participate In Practice
S Adrian Colbert (hamstring), G Joshua Garnett (toe), WR Marquise Goodwin (quadricep), G Mike Person (foot), LB Malcolm Smith (hamstring), T Joe Staley (not injury related – vet day)

Limited Participation in Practice
OL Erik Magnuson (hamstring), S Jaquiski Tartt (shoulder), CB K'Waun Williams (rib), CB Ahkello Witherspoon (ankle)

Detroit Lions Wednesday Practice

Did Not Participate In Practice
T Andrew Donnal (knee), G T.J. Lang (back)

Limited Participation in Practice
DE Ezekiel Ansah (shoulder)

Full Participation in Practice
RB LeGarrette Blount (shoulder), QB Matthew Stafford (shin)