The 32-year-old Morse hit .279/.336/.475 with 16 home runs and 61 runs batted in over 482 plate appearances with the Giants in 2014. He spent most of his time in the field in the outfield, but Morse does have over 1000 innings of experience at first base, where he will likely platoon with Garrett Jones (assuming Jones is not traded). Morse was average at first in 2014.
The Florida native was selected in the 3rd round of the 2000 MLB Draft by the Chicago White Sox. He has hit .281/.335/.473 in 10 big league seasons with the Mariners, Nationals, Orioles, and Giants.
Morse was worth 1.0 fWAR in 2014, and at an annual average value of $6 million, his signing makes a ton of sense for the Marlins, who have wanted to either platoon with the left-handed Jones (Morse is a righty) or perhaps replace him. If the Marlins get a good deal for Jones, there is absolutely no reason as to why they will not move him.
Morse has only received over 500 plate appearances once in his career, but that was in 2011, when he hit .303/.360/.550 with 31 homers and 95 runs batted in with Washington. He can definitely start in Miami if they want him to.
The Marlins have proven that they want to not only contend for the National League Wild Card in 2015, but also contend for the National League East division title. They have made a lot of moves this offseason, including the trades for Dee Gordon and Mat Latos, while now signing Michael Morse. They also extended Giancarlo Stanton to the $325 million deal.