Nolan Arenado and Manny Machado have always been on parallel tracks as ground-breaking third basemen. This season they've been dealing with their offensive declines. (Photo by Christian Petersen/Getty Images)

PHOENIX -- Nolan Arenado and Manny Machado have been inextricably tied by the hip since they broke into the Major Leagues, Machado with the Orioles in 2012 and Arenado with the Rockies in 2013.

Together they’ve combined for 15 All-Star berths, eight for Arenado and seven for Machado, and are on dual paths to the National Baseball Hall of Fame. The pair re-wrote how to play third base. Prior to their arrival it was a reactive position dominated by the quick hands and reflexes of those that came before them – Mike Schmidt, Brooks Robinson, Ken and Clete Boyer, and Eddie Mathews.

Arenado and Machado play third base like middle infielders, further back and with a lot of foot movement from side to side. They go across the foul line deftly and because of strong arms turn many a potential base hit into outs.

Even at their advanced ages for baseball – Arenado just turned 35 and Machado will turn 34 next month – they don’t seem to have lost a defensive step.