The Dolphins made two roster moves Tuesday when they signed wide receiver Courtney Gardner and waived wide receiver Terrell Sinkfield.

Gardner (6-3, 215), an undrafted rookie from Sierra (Calif.) College, agreed to terms with San Diego but never joined the team. Earlier this month Gardner and the Chargers mutually agreed to part ways so Gardner could take care of some "personal matters," according to the San Diego Union-Tribune.

Gardner, who didn't play college football last season, is regarded as a raw prospect because he hasn't faced top-notch college competition. He was a junior college All-America at Sierra where he totaled 61 receptions for 1,099 yards and 10 touchdowns last season as a sophomore in 2011.

Gardner was supposed to attend Oklahoma in 2012 but didn't qualify academically. He was then supposed to attend LSU but opted to declare for the NFL.

Sinkfield was an undrafted rookie free agent from Northern Iowa.

The Dolphins have a three-day OTA (Organized Team Activities) this week and among the things to look for will be the continuing health of starting cornerbacks Brent Grimes (Achilles) and Richard Marshall (back). Grimes only played one game last season and Marshall only played four. Both have participated in off-season workouts and expect to be healthy for training camp in July.