ARLINGTON -- The Texas Rangers will unveil their go-for-it rotation on Friday night, with left-hander Cole Hamels opening the show with a scheduled start against Pittsburgh at Globe Life Park.Right-hander Yu Darvish, the long-awaited component, is set to join the group on Saturday with his first start since undergoing Tommy John surgery on March 17, 2015.Hamels and Darvish have combined for six All-Star selections and six finishes among the top eight in Cy Young voting.If Hamels is the No.