BOSTON – The Red Sox front office just fired a shot heard ’round the AL East, pulling off a rotation revamp that’s got Fenway buzzing like it’s extra innings in October. In a move that screams playoff desperation wrapped in calculated aggression, Boston acquired veteran right-hander Luis Castillo from the Seattle Mariners in exchange for a package headlined by outfield prospect Jarren Duran and a pair of mid-tier pitching prospects. It’s the kind of bold pivot that could transform a rotation riddled with question marks into a Wild Card weapon, but only if the pieces click under the weight of sky-high expectations.