MIAMI -- The Miami Dolphins' off-season acquisitions at cornerback left no room for holdover Richard Marshall.
Marshall was released Tuesday, a person with knowledge of the decision said. The person confirmed the move to The Associated Press on condition of anonymity because the team hadn't made an announcement.
"I had a great time playing for the Dolphins," Marshall tweeted. "Appreciate all the love from the fans but it's time to move on. ... Good luck to all my boys ... have a safe and successful season."
The Dolphins added depth at the position with the off-season acquisition of veteran Brent Grimes and draft picks Jamar Taylor and Will Davis. Grimes is expected to start, and Davis has been impressive in practice this summer.
Returning cornerback Dimitri Patterson, an eighth-year pro, is also contending for a starting job.
Marshall started four games for Miami last year, but spent the final two months of the season on injured reserve with a back injury. The eighth-year pro, who has also played for Carolina and Arizona, had been scheduled to make $1.2 million this season.