Complex sentence: As a player, Leyva was an infielder in minor league baseball, Leyva began his managing career at age 25 with the Rookie-level Johnson City Cardinals of the Appalachian League in 1978.
Split into simpler sentences: As a player, Leyva was an infielder in minor league baseball. He began his managing career at age 25 with the Rookie-level Johnson City Cardinals of the Appalachian League in 1978.