Bush did not return after halftime last week, but an MRI was negative for structural damage. He is ranked No. 6 in the NFL with 302 rushing yards.
On the opposite side of the ball, starting cornerback Richard Marshall did not practice because of a back injury. He was listed as limited Wednesday.
Marshall suffered the injury two weeks ago against the Oakland Raiders, but he played against the Jets in Week 3. The Cardinals have the 29th-ranked passing offense (181 yards per game) in the NFL, but they also have one of the most dangerous receivers in Larry Fitzgerald. He was named NFC Offensive Player of the Week after nine receptions for 114 yards and one touchdown in last Sunday's win against the Philadelphia Eagles. Cornerback Nolan Carroll would move into the Dolphins' starting lineup if Marshall can't go.
Theoretically, the Cardinals aren't the worst team to face if you're down a starter in the secondary. But they continue to surprise with a 3-0 start. Quarterback Kevin Kolb is No. 3 in passer rating (108.6) despite being beaten out by John Skelton in training camp. Kolb hasn't thrown an interception, and no one ever wants to be shorthanded against Fitzgerald.
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