The Mariners ability to develop strong, sometimes elite bullpen arms has become somewhat of a normal thing in Seattle. They have taken borderline AAA guys and turned them into serviceable and sometimes high leverage arms. They have turned guys like Paul Sewald, Justin Topa, Gabe Speier, Erik Swanson, Drew Steckenrider, Penn Murfee and the list goes on and on, into very solid contributors at the major league level.
So why do they need to target these 3 bullpen arms? Well, you want proven, high leverage arms. Guys that you know will be there throughout the year and you will be able to count on. You would like to think Speier and Topa and Trent Thornton will be solid again but see Drew Steckenrider and that is point A of why you need to add 1 or 2, proven high leverage arms.