"Looking at all of the options and everything, I think Chris -- just like he pitched the first game of the year -- I think he carried that torch well," Showalter said of Tillman, who is 13-5 with a 3.26 ERA in 33 starts this season. "It just gives him the option to pitch two games in the first round."
Tillman, who will make his final regular-season start on Friday in Toronto, has allowed three earned runs or fewer in 20 consecutive starts, tying Steve Barber for the second-longest streak in club history.
The Orioles have won 11 of Tillman's past 13 starts, with the righty going 6-0 with a 2.06 ERA over that stretch and averaging 6 1/3 innings per start while holding opponents to a .201 batting average. A late addition to the AL All-Star team last year, Tillman has been a different pitcher since he was recalled midway through the 2012 season. He didn't earn a postseason start that year, but the learning experience was a valuable one.
"Chris has graduated," Showalter said. "It's been fun to have a good seat to watch it. He's a pro. He's turned into a guy I'm real proud of -- the way he goes about his business. It's not always perfection, but you feel good about him giving you a chance to win. ... He's been pretty consistent since Day 1."
Tillman has hit the 200-inning mark in back-to-back seasons and has matured from a top prospect to the O's frontline starter.
"There's a lot of people with good stuff, but he has it between his ears," said center fielder Adam Jones, who joined the Orioles with Tillman in a 2008 trade with Seattle. "That hunger, that want. I can see it in his eyes. Especially the second half, there's a look in his eye. He wants the ball, and when a pitcher has that, has that confidence, the only thing that can slow him down is himself."
Added Showalter: "Just his presence. You can tell he doesn't panic. He kind of knows who he is. He knows where to go. He has a lot of confidence in the endgame, so to speak. The sky's not falling after 10 pitches in a game."
The way the O's rotation is set up, it would seem likely that lefty Wei-Yin Chen and Miguel Gonzalez would be in line to start Games 2 and 3, respectively, though Showalter said the club will likely wait to announce the rest of the rotation until it knows its opponent.
Brittany Ghiroli is a reporter for MLB.com. Read her blog, Britt's Bird Watch, and follow her on Facebook and Twitter @britt_ghiroli. This story was not subject to the approval of Major League Baseball or its clubs.