The burden will fall upon Mets hitting coach Dave Hudgens to rebuild Chris Young, to turn this risky acquisition back into a value stock. Before the new Mets outfielder turns himself over to Hudgens, however, he received a tune-up from a valued set of eyes. “He did great,” Rod Carew told The Post, in a telephone interview Tuesday night, of his work with Young. “We took out a lot of thinking. I want him seeing the ball and reacting to the ball. … He was concentrating on what we were doing.” Working with Carew was “a nice treat,” Young said, also in a telephone interview with The Post. “It definitely can’t hurt.” As Mets general manager Sandy Alderson actually wielded a checkbook and competed for high-shelf free agents this winter, his first such opportunity in his fourth year as the team’s general manager, Young — at one year and $7.25 million — represented a considerably lower financial risk than Curtis Granderson (four years, $60 million) and Young’s 2013 A’s teammate Bartolo Colon (two years, $20 million). Yet, let’s face it: Many fans and media types professed the most confusion over Alderson’s commitment to Young, who put up an underwhelming .200/.280/.379 slash line with Oakland last year. In all, Young’s OPS has decreased each of the last three seasons. His downward trend prompted Young, who turned 30 in September, to change up his offseason routine. He started working a month earlier than normal, in late October as opposed to Thanksgiving — this even though his A’s played in the American League Championship Series — and he reestablished a relationship with an old friend while introducing himself to a new acquaintance. The old friend is James Cooper, a Houston-based trainer with a primary background in football and mixed martial arts who helped rebuild Vikings running back Adrian Peterson after Peterson tore the ACL and MCL in his left knee. Young, who lives in Houston, reunited with Cooper after about 10 years apart. They worked together five days a week, focusing on Young’s core strength. “I want to feel more athletic on the field,” Young said.