Pittsburgh Pirates first base prospect Mason Martin has made some significant changes in his stance and swing which has led to his most productive season since 2019 Pittsburgh Pirates minor league first baseman Mason Martin had to make a change after his abysmal 2022 season. Martin turned in a .210/.287/.410 line with a .303 wOBA, and 79 wRC+. Martin had a respectable .200 isolated slugging percentage and 9.6% walk rate, but struck out well over a third of the time (35.9%). There were pretty much no expectations for Martin to rebound with very clear issues in his game, but Martin…