"We may see everything Round Rock has before it's over," manager Ron Washington said.
With the young arms being called up, the Rangers continue to look at the possibility of trading veteran relievers Neal Cotts and Jason Frasor before the July 31 non-waiver Trade Deadline. There is interest in both, even though Frasor has allowed five runs over 3 1/3 innings in his last five outings.
"He has just hit a bad patch," Washington said. "Every time he throws a pitch that doesn't go where he wants it to go, it gets hit. When you're going good, they pop it up or miss it. It happens. We'll keep giving him the ball and things will fall back into place."
West was 2-2 with a 4.40 ERA 19 games at Round Rock. In 24 innings, he allowed 34 hits and eight walks while striking out 28. He had a 2.79 ERA in his last eight outings.
West was originally drafted by the Rangers in the second round of the 2007 First-Year Player Draft as an infielder out of Houston Bellaire High School. In 2011 he became a pitcher because he had a fastball that was registering 100 mph. But he missed almost all of last season after undergoing Tommy John elbow reconstruction surgery Aug. 22, 2012.
"It has been eventful, that's for sure," West said. "It has been a dream ever since I was a little kid. I'm excited to do my job and help this team win."
In Friday's 15-6 loss, West made his Major League debut, striking out one over two perfect innings.
Irwin, who allowed three runs in four-plus innings in an 8-3 loss to the Astros on Tuesday, was scheduled to pitch Sunday. The Rangers haven't announced a replacement, but it will likely be Baker unless he is needed out of the bullpen before then.
Washington said the Rangers have no plans to bring Yu Darvish back on three days' rest. Darvish is expected to start next Friday in the first game after the All-Star break.
T.R. Sullivan is a reporter for MLB.com Read his blog, Postcards from Elysian Fields and follow him on Twitter @Sullivan_Ranger. Grace Raynor is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.