Kammala wannan jumla: Kafin ranar ƙarshe na musayar 2013 <unk> 14, Blues sun yi musayar Halák, Chris Stewart, William Carrier, zagaye na farko a cikin
2015 da kuma zagaye na uku na zagaye na zagaye a shekarar 2014 zuwa Buffalo Sabres a musayar Ryan Miller da Steve Ott a ranar 28 ga Fabrairun 2014. Halák bai bayyana a cikin wasa don Sabres ba kuma a ƙarshe an yi ma'amala tare da zagaye na uku na zaɓaɓɓu zuwa Washington Capitals a musayar Michal Neuvirth da Rostislav Klesla a ranar ƙarshe na musayar. Halák ya yi ado don Sabres a matsayin mai tsaron gida a cikin wasa ɗaya, yana mai da shi ɗan wasa na 10 a tarihin Sabres don yin ado ga ƙungiyar a wasan kakar wasa ta yau da kullun amma ba wasa ba.