Mickey Callaway noncommittal on Edwin Diaz as closer: 'I don't think anybody is locked into roles'Diaz gave up a two-run home run on Saturday night8/4/2019, 3:58 AMAug 3, 2019; Pittsburgh, PA, USA; New York Mets relief pitcher Edwin Diaz (39) pitches against the Pittsburgh Pirates during the ninth inning at PNC Park. The Mets won 7-5. Mandatory Credit: Charles LeClaire-USA TODAY Sports / Charles LeClaire