Miami Dolphins 2015 Year in Review: The Coaching Carousel

After their seventh straight non-winning season, are the Dolphins set to turn things around?

After three straight seasons without a winning record and a 1-3 start to the 2015 season, the Dolphins fired head coach Joe Philbin and replaced him with Dan Campbell.

After failing to score more than 20 points during the first four games, Miami’s offense looked rejuvenated under Campbell. They averaged 41 points in his first two games and outscored their opponents by a combined 46 points across those two wins.

The honeymoon was short-lived, and the Dolphins scored more than 20 points only one more time all season -- in a Week 14 loss to the New York Giants.

The end result was a 6-10 record and a 28th-place finish in our power rankings.

Using basic and advanced statistics, including our signature metric, Net Expected Points (NEP) -- which measures how each play contributes positively or negatively to the outcome of the game -- let’s look at how the Dolphins’ 2015 season played out.

What Went Right

The Dolphins found success when they leaned on Lamar Miller as their workhorse running back, going 6-1 in games which Miller had 13 or more carries. Although running back carries don't necessarily mean causation, Miller really was a bright spot on the offense.

Among 44 backs with at least 100 carries, Miller ranked 17th in Rushing NEP (-2.18). Per carry, he and @jay ajay (-0.34 Rushing NEP) each scored a -0.01 mark.

Jarvis Landry followed up his breakout rookie year by finishing his sophomore campaign with the fourth most receptions (110) in the NFL. Behind Landry, Rishard Matthews’ 43 receptions were the second most on the team, and his 0.98 Reception NEP per target ranked fifth among all players with 50 or more targets.

The offense as a whole only lost seven fumbles all year, which was tied for the second-fewest in the league behind San Francisco.

The defense was led by Pro Football Focus’ second-ranked defensive line, who benefited from the addition of free agent Ndamukong Suh. He finished the season with 6 sacks to go along with 61 tackles, which was his highest since his 66 during his rookie year. Additionally, Cameron Wake rebounded from a slow start to finish with seven sacks over his final three games before ending the season on injured reserve.

However, their rushing defense ranked just 15th in the NFL on a per-play basis after adjusting for schedule strength, per our metrics.

What Went Wrong

In football, it all starts up front, and that's exactly where the problems began with the Dolphins' offense.

Pro Football Focus graded the Miami offensive line as the second-worst unit in the NFL. Their 45 sacks allowed were the eighth-most in the NFL last season, and they were ranked dead last in run blocking.

At quarterback, Ryan Tannehill's 0.05 Passing NEP per drop back ranked 27th among the 36 quarterbacks with 200 or more drop backs in 2015. It was the first time in his career that his Passing NEP per drop back has fallen from the previous season.

Landry was a reliable receiver for Tannehill, but he averaged only 10.5 yards per catch. Among all players with 50 or more targets, his 0.49 Recption NEP per target ranked 80th, and he ranked last among 32 receivers with at least 100 targets. After being selected with the 14th overall draft pick, DeVante Parker was expected to start along with Landry but had his rookie year hampered by injuries and finished with only 26 catches.

Free agent acquisition Jordan Cameron disappointed as well, with his 0.50 Reception NEP per target ranking 24th out of 28 tight ends who saw 50 or more targets in 2015.

Despite the team’s success when leaning on Miller, he received 12 or fewer carries in nine games, and the Dolphins lost every single one of them. The small workload could have contributed to Miller’s decline in efficiency, as he finished with a -0.01 Rushing NEP per rush compared to 0.13 on 215 carries in 2014.

The struggles translated over to the other side of the ball as well, and Miami’s 138.09 Adjusted Defensive NEP ranked 31st in the league.

Wake's slow start that I mentioned earlier, was highlighted by his failing to record a sack through the first four games of the season, and he only appeared in three games after that before being placed on injured reserve. The Dolphins' pass rush struggled without him, as they finished the year ranked 25th in the NFL with 31 sacks.

And while the offense was able to secure the football, the defense recovered a league-low three fumbles all season.

What’s to Come

Miami has a new head coach in Adam Gase, who has spent the last three seasons as the offensive coordinator in Denver and Chicago under John Fox.

Miller won’t get a chance for more carries with the Dolphins because he left for Houston. Miami has been rumored to be pursuing a trade for a running back and could also acquire one in the draft or free agency, but 2015 fifth-round draft pick Jay Ajayi is the leader in the backfield for now.

The offense will also be without Matthews, who left for Tennessee, which puts even more pressure on Parker to remain healthy and have a breakout season.

On defense, Miami will move forward without Brent Grimes who they have replaced with Byron Maxwell. Kiko Alonso also came with Maxwell via trade, and Mario Williams was brought in to help replace the pass rushing of the departed Olivier Vernon.

Williams had only 5 sacks last season in Buffalo after averaging 12 per year over the previous three seasons.

The coaches and players alike will have to improve their performance in order for Miami to avoid an eighth straight season without a winning record.