There isn't much precedent for what happens when a young, elite wide receiver switches teams. I see only two legitimate comparables to Marshall moving on to Miami:
Harold Jackson led the league in receiving yards in in 1969 and then again in 1972 at the age of 26; he was traded to the Rams in the following off-season in a package for QB Roman Gabriel. Jackson went on to have a strong career with the Rams, although he never quite reached the same heights that he did with the Eagles. Jackson did lead the league in touchdown receptions for Los Angeles in 1973. John Jefferson led the league in touchdown receptions his first and third seasons in the league with the Chargers, gaining over 1,000 receiving yards each year. At the age of 25, Jefferson held out of Chargers training camp and was eventually traded to the Packers. In his fourth season, 1981, Jefferson had just 632 yards in 13 games. Jefferson gained just 2,253 receiving yards in four years with the Packers, and was out of the league a season later.
Leaving ancient history aside, Marshall has done well under different coaching staffs, playing in different schemes and catching passes from different quarterbacks. He transitioned seamlessly (at least on the field) from Cutler and Shanahan to Orton and McDaniels; now he moves East to play with Henne and Sparano. Can he have his fourth consecutive 100 catch season?
The Dolphins ran the ball more often than any other team outside of the Jets and the Panthers last year. Because Miami ran an absurdly high number of plays in 2009 (1,088, the fifth highest number of the decade), the Dolphins also still threw 545 pass attempts last season. But the Dolphins are clearly a running team; or is it, clearly "were" a running team? The trade for Marshall signaled the front office's realization that the forward pass is a good thing, and Miami won't get very far without a capable passing attack to complement their great running game.
That's good for Dolphins fans. Is it good for Marshall's fantasy numbers? Miami's top two receivers last season, Davone Bess and Greg Camarillo, are possession receivers who won't add much to a team that has Brandon Marshall. Brian Hartline adds a slightly different dimension but isn't a real threat to Marshall. Anthony Fasano isn't a big play tight end, which leaves only the running backs as explosive threats to steal touches from the newly acquired Bronco. If possible, the supporting cast in Miami is even less likely to compete with Marshall than the supporting cast in Denver. When Miami does pass, Marshall will be priority A, B and C. And the strong running game should allow Marshall to get deep more often than he did in 2009 with the Broncos. I think Marshall in 2010 will look a lot like some of Steve Smith's years in Carolina or Roddy White's 2008 season with the Falcons. He can still have strong production on a running team because no one is there to steal targets. Because of that, I view Marshall as a low-floor (assuming, of course, he stays out of trouble in South Beach, no easy task), high-upside pick at the end of the second round in standard leagues.
Questions, suggestions and comments are always welcome to stuart@footballguys.com.