3 Former Mariners players we'll be glad are gone, and 2 we'll wish stayed
Seattle Mariners players we're glad to see gone: Donovan Walton
This one is a bit different. I'm not listing him here because I was glad to see him leave. In fact, I was actually a bit upset. He was a guy that I really liked, and I have a soft spot for anyone that I've ever interviewed. I was hopeful that he could stick around the Mariners in an eventual Moore or Haggerty role, filling multiple spots off of the bench. Instead, the Mariners shipped him off to the Giants for Prelander Berroa.
That right there is the reason.
The Mariners got Berroa, who has looked like a different pitcher since coming over to the Mariners. He has vaulted up the prospect rankings, and sits well within the Mariners top ten, and even top 5, with his nasty stuff. He can touch 100, but may end up being a reliever in order to take advantage of that velocity and limit the control issues that he can have. Without trading Donovan Walton (I'm sure they could've made the deal for a different player, though) the Mariners wouldn't have Prelander.