‘We need a spark’: Yankees battling to keep a slide from becoming a spiral

NEW YORK — When injured outfielder Harrison Bader walked into the Yankees’ clubhouse for the first time on Aug. 3, he couldn’t help but wonder what his new teammates were thinking.

“I’m sure everybody in here was like, ‘We just traded for this guy in a boot?'” said Bader, who despite dealing with plantar fasciitis was acquired from the St. Louis Cardinals at the deadline. “‘Are you serious?'”

That sense of unease is the mood in the Yankees’…