Dolphin dominance: Real or mirage?

The Los Angeles Rams were one of the Super Bowl favorites going into this season. They've started 4-0 and sit at No. 1 in the ESPN NFL power rankings.

The Kansas City Chiefs have the most exciting offense in the NFL. Patrick Mahomes set an NFL mark by throwing 13 touchdown passes in the first three weeks of the season. The Chiefs are 3-0 and now are considered one of this season's Super Bowl favorites.

But there's one more unbeaten team left, and it's not a team anyone would have expected before the season began.

Coming off a 6-10 season in 2017, the Miami Dolphins have started the 2018 season with three straight wins. None of the wins have come by double digits, but a closer look at the play-by-play shows the games haven't been that close, either. As a result, the Dolphins rank No. 2 in Football Outsiders DVOA ratings after Week 3. They haven't just been a good team, but a balanced one. They are in the top 10 in both rushing and passing on offense, against the run and the pass on defense, and on special teams.

How are the Dolphins doing it? And can they keep this up?