Dodgers levelheaded Will Smith keeps getting better

LOS ANGELES — They have become baseball’s unicorns – catchers who handle the difficult defensive responsibilities of that position while also contributing offensively. Last year, catchers across MLB combined for a slash line of .228/.295/.368. Each of those parts – batting average, on-base percentage and slugging percentage – as well as the OPS of .663 were the lowest for any position on the field and it wasn’t even close. Only three catchers had an OPS over .800 last year – Philadelphia’s J.T. Realmuto, Baltimore’s precocious Rookie of the Year runner-up Adley Rutschman and the Dodgers’ Will Smith. “I think he’s…