The pair, who both arrived Sunday and are competing for roster spots, both played winter ball and are pretty much in "game shape." While Monell is competing primarily with Steve Clevenger to back up catcher Matt Wieters, Aceves is a bullpen option and the O's are giving the fiery right-hander a fresh slate.
"I've learned through the years I make up my own mind about people," Showalter said when asked about Aceves, who has had well-documented run-ins with teammates and managers. "Some people are a product of their environment. I'm pretty confident about our environment. "It's very obvious, [pitching coach] Dave [Wallace] and I were talking [Sunday] whether it be PFPs and drills and this and that, when he gets on the mound and puts a baseball in his hand and he's pitching, you see why he has been in demand. He had a number of offers and he came here."
There are a lot of players in camp who have played with Aceves, who has a good chance to make the club as a non-roster invitee. Showalter said he made a favorable impression in an early meeting and that it's a tough balancing act to trust the solid clubhouse environment as well as protect it.
"That's the weighing," he said. "Protective of it, but you're confident of it. Peer pressure is pretty good. My barometer of players is, if they don't care what their teammates think, you've got a problem. That's usually the indicator. But until you've walked a mile in a man's shoes and been in some of his recent environments …
"There have been some good baseball people who have had this guy who have had some bumps in the road. I'm not blind to that. I'm not any smarter than they are, but I'm real confident that, if it's there, we can find it."
Brittany Ghiroli is a reporter for MLB.com. Read her blog, Britt's Bird Watch, and follow her on Twitter @britt_ghiroli. This story was not subject to the approval of Major League Baseball or its clubs.