DAVIE, Fla. — Run defense has become a major concern for the Miami Dolphins (7-5), and it’s even more of a concern considering Baltimore (7-5) brings running back Justin Forsett to town.

The Dolphins have allowed 478 yards rushing – 201 at Denver, 277 at the New York Jets – in the last two weeks.

And Forsett has 1,009 yards rushing. Problems could be rising for the Dolphins, particularly if they don’t tackle better. Miami has fallen to No. 21 in run defense at 118.6 yards per game.

“We have to tackle better,” coach Joe Philbin said. “This game is not overly complicated. If you can run the ball that effectively, they are going to continue to do that. We have to improve, without a doubt.”

The Dolphins have allowed four 100-yard rushers so far this season – Jacksonville’s Denard Robinson (108), Kansas City’s Knile Davis (134), Denver’s C.J. Anderson (167) and the Jets’ Chris Johnson (105) – and that’s double the total from last season.

The coaches say poor run fits and poor tackling are at the root of the problem in every case.

“When you watch the tape a couple of instances, it’s not every single time we go to tackle,” defensive coordinator Kevin Coyle said, “but it’s just some of the basic fundamentals have been missing at times, whether a guy leaves his feet when he doesn’t have to, maybe he doesn’t wrap up when he should wrap up with his arms. Maybe he doesn’t accelerate his feet on contact.

“There are a lot of different things that have shown up, and usually as is always the case, it’s never necessarily one thing.”

The defensive line, the strongest area of the team, and the linebackers have been mostly at fault when it comes to the run defense. They’ve been blown off the line of scrimmage, suspect at the point of attack, and their fundamentals have been lacking, as Coyle said.

“Usually missed tackling comes from fundamentals and being able to gather yourself, get under control and take the proper angle,” he said.

The Jets also presented a new problem to Miami’s run defense – reverses.

New York thrived with at least 40 yards on the three reverses it used against Miami.

“I think there are isolated break downs that we need to get fixed,” Coyle said. “Some of the plays that have broken out on us, like (against the Jets), were not your conventional run plays, when you’re talking about reverses and things of the nature. We’ve got to get some of that cleaned up.

“Some of the other plays that we gave up during the course of the game, we really need to get back to basics and do a better job of fitting the run game. I believe we’re going to do that.”

SERIES HISTORY: 10th regular season meeting. Miami leads series, 5-4. The Ravens won the last meeting, 26-23, in 2013. The Dolphins tied the game at 23 in the fourth quarter on Reshad Jones’ 25-yard interception return for a touchdown. But the Ravens got a 44-yard field goal from Justin Tucker with 1:43 left for the victory. The Dolphins gave up six sacks. Interestingly, the Ravens have knocked the Dolphins out of the playoffs in Miami’s last two appearances – 2008 (29-9) and 2001 (20-3).

NOTES: WR Brian Hartline (knee bruise) went through Wednesday’s walkthrough practice. Hartline missed the second half of the Jets game. .. OL Nate Garner (illness) missed Wednesday’s practice. His status for Sunday’s game isn’t known. … CB Cortland Finnegan (ankle) participated in Wednesday’s practice. Finnegan has missed the last three games. … CB Jamar Taylor (shoulder) and LB Jonathan Freeny (hamstring) have been ruled out for Sunday’s game. .. OL Nate Garner missed Wednesday’s practice. … TE Charles Clay (hamstring) was limited in Wednesday’s practice. … WR Mike Wallace (chest) and LT Ja’Wuan James (neck) were also limited in Wednesday’s practice.