PEORIA, Ariz. -- D-backs right-hander Bronson Arroyo was scratched from his Tuesday start due to tightness in his back.
The decision was made Monday when Arroyo began experiencing the discomfort.
"I didn't see him," D-backs manager Kirk Gibson said when asked Tuesday morning how Arroyo was doing. "I think he's still pretty jammed up. I don't know what's going on with that. He's not going to do any throwing today I know that."
Arroyo was already a bit behind the other pitchers because he did not sign his free-agent contract until a few days after camp opened.
The 37-year-old is known for his durability, having made at least 32 starts in each of his nine seasons as a full-time starter.
"Not at this point," Gibson said when asked if he was concerned about Arroyo's condition. "We've got a long ways to go. He's never really had a history of missing starts so I feel confident he'll be fine."
Ross will take it easy on basepaths
PEORIA, Ariz. -- D-backs outfielder Cody Ross did not play in a simulated game Tuesday, as the club had planned, because the game was canceled.
Initially the team was going to have a simulated game on a back field to get right-hander Randall Delgado some work, but when Bronson Arroyo was scratched from his start Tuesday the team had to use Delgado to start, so the game was canceled.
Ross, who fractured and dislocated his right hip last August, could try sliding in a week or so.
"He could come fast," D-backs manager Kirk Gibson said. "The big thing with him is comfort level with what he does. He's got a ways to go yet."
When he does return to action, the D-backs would like to see him take it a little easier on the bases.
"We have to try and give more thought to around the bases," Gibson said. "He's got to be more controlled around the bases."
Roster moves leave D-backs with 53 in camp
PEORIA, Ariz. -- The D-backs trimmed their number of players in camp by 15 on Tuesday.
Pitchers Chase Anderson, Charles Brewer and Alex Sanabia were optioned to Triple-A Reno while left-hander Santos Rodriguez was optioned to Double-A Mobile.
The team also reassigned 11 non-roster players to Minor League camp, including Andrew Chaffin, Mike Freeman, R.J. Hively, Justin Greene, Sean Jamieson, Evan Marzilli, Willy Paredes, Steven Rodriguez, A.J. Schugel, Seth Simmons and Jess Todd.
The moves leave the D-backs with 53 players in camp.
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.