When you think Texas Rangers, you think Nolan Ryan. He played for other teams, but it seems he is most often identified as a Ranger. He threw no-hitter #7 as a Ranger, he put Robin Ventura in a headlock as a Ranger and he retired as a Ranger.
Charlie Hough is the man behind perhaps the most famous knuckleball of all-time (either him or Phil Niekro). Hough remarkably played 25 MLB seasons, including 11 with the Rangers. He is the franchise leader in innings pitched (2,308) and wins (139).
Fergie Jenkins threw over 1,400 innings in a Texas Rangers uniform and had a .563 winning percentage. He did play the majority of his career with the Chicago Cubs; however, he undoubtedly left his mark in Texas.
Someone in recent memory…Yu Darvish is fourth in the all-time rotation. Darvish spent each of his five years with the team as the ace. Expectations were off the charts for him after coming over from Japan and he certainly did not disappoint. While it would have been nice to see more playoff success, Darvish contributed plenty to multiple playoff appearances. In just 782 innings pitched with Texas, he ranks fourth all-time in strikeouts (960) and fourth all-time in ERA (3.42).
Finally, Kevin Brown began his career with Texas and went on to give the franchise eight years of quality work. Brown ranks 5th in team history in innings pitched and wins.