Cashner threw five scoreless innings in an extended spring camp game on Monday and had another bullpen session on Wednesday.
"It was really good," Cashner said. "I threw 40 pitches or so, and everything was good. I feel I am where I need to be."
Texas is holding off making an official announcement. The Rangers still have Nick Martinez, and he could start on Saturday if necessary.
"There are always things that can happen," Banister said. "We want to make sure every day, [Cashner] is healthy and ready to go."
Bush to rejoin Rangers
Reliever Matt Bush is expected to rejoin Texas in Seattle. He is sidelined with soreness in his right shoulder and had a cortisone injection on Wednesday in Dallas.
The Rangers will sit down with Bush on Friday, see if the cortisone injection helped and then plan accordingly. The club is hoping Bush can get through a long-toss session on Saturday and the shoulder holds up.
Texas is getting its first real look at the advantages of the new 10-day disabled list. Bush last pitched on Sunday, so putting him on the disabled list and backdating it to Monday would mean getting him back on Thursday when the Rangers return to Arlington.
"We'll look him in the eyes and see how he feels," Banister said. "If he can go through the long-toss program on Saturday, that will be a benchmark. We are not ruling anything out. Our main objective is to make sure he feels good and is ready to go."
• Jose Leclerc recorded his first save on Wednesday at age 23 years, 114 days. Since 1988, the only Rangers pitchers who were younger when they recorded their first save were Neftali Feliz in 2009 (21 years, 105 days) and Keone Kela in '15 (22 years, 62 days).
• Infielder Hanser Alberto, who is on the disabled list with a sore right shoulder, is expected to resume a throwing program. He is currently in Arizona going through all other baseball activities except hitting.
• Catcher Brett Nicholas, also in Arizona recovering from left knee surgery, is expected to start catching bullpen sessions this weekend and begin building up to games next week.