Second base: Jackie Robinson, 57.2 fWAR
As if there could really be anybody else at this spot. Robinson, one of the most recognizable names in the history of baseball, is a legend in multiple respects both on and off the field.
After debuting in the Negro leagues with the Kansas City Monarchs in 1945, Robinson made his way to the Brooklyn Dodgers, becoming the first ever African-American player to appear in an MLB game. Naturally, he pretty much instantly became a must-see talent, leading the NL in stolen bases in his rookie year en route to a fifth-place finish in the MVP voting and a Rookie of the Year trophy.
In a brief but legendary career, Robinson spent just 10 years on the Dodgers, but cemented his name into the all-time record books in more than one way. In 1,382 games for the club, he hit 137 home runs, drove in 734, stole 197 bases, and posted a career .311 batting average. He was an absolute on-base machine as well, posting a career .409 OBP, .883 OPS and 132 OPS+. A stat that doesn't get talked about enough when it comes to Robinson is the fact that he walked 740 times in his career while striking out only 291 times. Absolutely unreal.
Unfortunately, Robinson passed away in 1972 at the age of 53 and was not alive to see himself get elected into the MLB Hall of Fame, which came in 1962 after he received 77.5% of the votes his first time on the ballot.
Today, Robinson's number is the only one retired by every single MLB team and his legacy continues to live on. His story of reaching the majors is an all-time great one, and it's only fitting that he's statistically the best second baseman to ever do it for the Dodgers.