"But that's subject to change," manager Ron Washington said as the Rangers are waiting to see how Harrison recovers from his bullpen session.
The Rangers appear to be leaning toward Harrison starting on Friday. Lewis would follow on Saturday with Ross being pushed back to Sunday. That would mean Yu Darvish, Martin Perez and Lewis facing the Athletics during their three-game series that starts on Monday in Arlington. The Athletics are scheduled to pitch Sonny Gray, Scott Kazmir and Jesse Chavez in that series.
Ross allowed seven runs in 5 1/3 innings in his last start against the White Sox on Sunday, but the Rangers aren't interested in skipping his turn in the rotation. He had a 1.00 ERA through his first three starts.
"He has been one of our better pitchers," Washington said. "We're not going to skip him all together."
Harrison won 18 games for the Rangers in 2012 and was their Opening Day pitcher in 2013. But he was shut down after two starts because of a herniated disk in his lower back. He twice underwent surgery on April 23 and May 1 and did not return the rest of the year. He had an additional surgery on Sept. 9 on his right non-throwing shoulder to alleviate thoracic outlet syndrome.
T.R. Sullivan is a reporter for MLB.com Read his blog, Postcards from Elysian Fields and follow him on Twitter @Sullivan_Ranger. This story was not subject to the approval of Major League Baseball or its clubs.