Offensive coordinator Mike Sherman said this week that he envisioned the Dolphins averaging 75 to 78 snaps per game on offense. They haven’t even come close.

Despite generally not huddling during games, the Dolphins are averaging 62.5 plays per game, barely above last year’s 61.8. Conversely, Dolphins opponents are averaging 68.9.

The most obvious explanation is the Dolphins’ inability to move the ball consistently. Miami ranks 29th in total offense, and its 173 first downs are sixth-worst in the league. By comparison, NFL teams — on average — had 200 first downs entering this week’s games.

The Dolphins are 20th in third-down efficiency, but Ryan Tannehill’s has the league’s second-worst quarterback rating on third downs. That clearly translates into fewer plays.

“Our play count is nowhere near where it needs to be,” coach Joe Philbin said. “That’s a reflection of our third-down performance or lack thereof. Say you average 12 possessions a game. If you’re running 55 plays in a game, that’s four to five plays per possession.

“It doesn’t add up to the type of tempo or fast pace you want to get going. We’re not where we need to be in regard to tempo. The 10-play possession drives just aren’t there.”

Philbin indicated the Dolphins ideally want to get first- and second-down plays a bit more than halfway into the 40-second play clock. The Dolphins haven’t always been able to do that when Tannehill changes the play.

“If you get it [with 18 seconds left on the clock], that’s great in a normal down and distance,” he said. “On third down, you’re usually taking a little longer and maybe we’re getting some of those plays snapped under 10.”

Philbin was asked if it’s realistic for the Dolphins to play at the pace the Patriots do when they use the no-huddle.

“The faster, the better,” he said. “Once we can get things rolling a little bit, sure.”

The play-count issue came up this week when Sherman was asked whether it’s difficult to give Lamar Miller snaps as a third running back.

“We’re not getting a whole lot of snaps in the game,” Sherman said. “If we were getting 65 to 70 snaps, which I envisioned — actually, I envisioned 75 to 78 snaps — then I think there’s more snaps to be got.”

THIS AND THAT

• The Dolphins used linebacker Koa Misi as a defensive end more in the Buffalo game than previous ones, trying to seize on his pass-rushing skills. Misi had a sack against the Bills and has 2.5 for the season.

“We consider Koa to be in that group that we’re going to try to rotate at the right end spot, depending on the game,” defensive coordinator Kevin Coyle said. “Last week, there was very, very little base defense the whole game. They were in three wide receivers or more for the better part of the game. That’s where we make decisions: ‘Hey, we’re going to make sure that he’s getting reps or he’s going to be just watching from the sideline.’ And he is one of our better rushers.”

• Tannehill, whose passer rating ranks ahead of only Brandon Weeden, Matt Cassel and John Skelton, said: “I really need to play well for four quarters, not just part of the game, but for four quarters and get us out of this slump.”

• Though the Dolphins rank third in the league in third-down defense — allowing opponents to convert 33.1 percent of their third-down plays — they’re the worst in fourth-down defense, with nine of 10 successful conversions against them.

• No Dolphins were listed as out or doubtful on the injury report; Austin Spitler (ankle) is questionable. Karlos Dansby (biceps), Mike Pouncey (ankle), Anthony Fasano (hip), Jimmy Wilson (ribs) and Brandon Fields (knee) are probable.

Seven Seattle players are probable, including running back Marshawn Lynch.