Miami Dolphins offensive coordinator Mike Sherman knows exactly why rookie QB Ryan Tannehill is developing ahead of schedule: rigorous practices.

“I’ll go to [coach Joe Philbin] sometimes and say, ‘Can we just practice against a regular, vanilla [defense] so I can practice some of this other stuff?’ ” Sherman said. “So if you can make it through practice, then the game should be a little bit easier, particularly going against our defense.”

Tannehill became one of three rookies in NFL history to crack the 1,000-yard passing mark through four games, joining Carolina’s Cam Newton and Washington’s Robert Griffin III. The eighth-overall pick in April’s draft threw for 431 yards -- one yard shy of Newton’s rookie record set last season -- in a 24-21 overtime loss to the Cardinals last week.

One of Tannehill’s biggest adjustments has been his ability to identify the blitz before the snap and get the ball in the hands of his hot receiver. The former Texas A&M star repeatedly found players running quick slants and crossing routes to counter the Arizona pressure packages.

“We always practice pressure and blitz, but I just saw Ryan this week mature in how he handled it,” Sherman said. “He stepped up in the pocket making throws, and thought this past week of practice was his best week of practice. He just seemed more confident and sure of himself. He’s always been confident, but even more so. I thought going into this game that he was as ready as he’s ever been, and I think he proved that.”

Walking wounded: The Dolphins have severely key players nursing injuries ahead of Sunday’s game against Cincinnati.

RB Reggie Bush (hip), LB Austin Spitler (groin) and DT Tony McDaniel (knee) were limited in Wednesday’s practice while LB Kevin Burnett (foot) and CBs Nolan Carroll (Achilles) and Richard Marshall (back) sat out with their ailments. The injuries to Carroll and Marshall forced the team to sign CB De’Andre Presley from the practice squad.

Miami also signed DB Julian Posey to the practice squad.

Tight end trouble: Miami TE Charles Clay has just one catch for two yards this season -- and Sherman blames his play-calling.

Clay, who had three touchdowns during an injury-riddled season last year, has been less involved in the team’s offense and dropped a deep pass against Arizona last week when he was drilled on a seam route.

“He’s running great routes." Sherman said. "We’ve just got to make sure he gets the ball. I think he works hard in practice. He has a lot of talent. I’ve just got to find a way to get him going, and I haven’t done a very good job of that yet. That’s on me to get him going, because he’s more than willing.”

For more up-to-the-minute news and analysis on the Miami Dolphins from blogger Dave Carey, follow @CBSDolphins