The Red Sox placed Manny Ramirez on irrevocable waivers for several reasons.
Ramirez talked to the club at the end of the season and expressed that while he likes the Red Sox and Boston, he wouldn't mind seeing what there was in a trade, with his home (New York) an enticing option. If someone like the Yankees were to take the $100 million over five years, it would free the Red Sox to make several other moves.
With a number of teams looking to pare payroll, the Red Sox could take Curt Schilling, Matt Mantei and Junior Spivey from the Diamondbacks. Or they could possibly take on contracts from teams such as Houston, St. Louis or the White Sox.
When Rangers owner Tom Hicks approached the Boston ownership about Alex Rodriguez, he was told that Texas would have to take Ramirez. The Red Sox were told that the Rangers had no interest in Ramirez.
When Ramirez talked to Red Sox officials, they offered to let him out of his contract so he could become a free agent. Obviously he declined, as agent Jeff Moorad knows that the current market might bring four years, $50-60 million, in contrast to the five years, $100 million on his existing deal.