The turning point of Marcus Semien’s career occurred May 17, 2015, in the weight room of the Oakland Coliseum.



Semien wasn’t present, mind you. No, he was out on the field, making two errors in a 7-3 loss to the White Sox, convincing the Athletics’ lead decision-maker, Billy Beane, to stage an intervention.



Beane, following his usual practice of working out during home games, turned to his top assistant, David Forst, in the weight room and sounded an alarm.



We’ve got to get Wash in here, right away.



“Wash” was Ron Washington, the highly regarded infield instructor who had helped dramatically improve the defense of former A’s infielders Eric Chavez and Miguel Tejada in his previous stint with the club from 1996 to 2006.



Washington was available — he had resigned as Rangers manager in September 2014, saying he had been unfaithful to his wife. He still remembers what Beane said to lure him back...