"I've had the opportunity to be around a lot of special pitchers but tonight you got to see one of the really good ones," said Jason Jaramillo, Walker's catcher on Tuesday night. "He's got composure, he's got the stuff, he's got the talent. He's really blessed, so just seeing him a couple days now, he's special."
Despite his obvious success, Walker said that his first time facing Triple-A hitting was a learning experience for him, and that he will have to learn to pitch to shrewder batters.
"A lot of them are very patient, they don't miss the fastball, they put the ball in play a lot," Walker said. "They don't chase after the curveball in the dirt or a fastball that's up, so they're a lot more patient than Double-A hitters."
It was an auspicious beginning for MLB.com's No. 2 right-handed pitching prospect. The 20-year-old has blazed through the organizational ranks after the Seattle made him their first pick in the 2010 First-Year Player Draft, the 43rd selection overall.
After struggling when he was initially called up to Double-A a year ago, Walker retooled his curveball during Spring Training and has pitched like a No. 1 starter since. This year he dominated the Southern League, ranking first in strikeouts with 96 and third in the league in opposing batting average (.195).
"He's much more mature physically than a year ago, to think that he's here doing this at age 20 at this level is really, you can really fantasize about what's going to happen in the future with him," Tacoma manager John Stearns said. "He's got a really high ceiling, his ceiling is up there as good as I've seen."
On Friday, the Mariners promoted Walker to Tacoma, where he is the youngest player in the Pacific Coast League. In fact, the precocious pitcher is the youngest member of the Rainiers rotation since Felix Hernandez -- another flame-throwing phenom -- back in 2005.
"This is an exciting moment for our organization," Stearns said before the game. "We don't want to let him know that too much, but everyone is really excited about him being here in Triple-A at this early age. We're going to do everything we can to have him succeed this first year here and move forward from there."
With such lofty expectations, Walker will have to deal with the pressure and anticipation of developing only 35 miles south of Safeco Field. While Mariners fans eagerly await his callup, Walker knows that he can't get ahead of himself.
"It's right there so it's very exciting, but at the same time you've just got to take it one day at a time, so I've been doing that a lot," Walker said. "I know last year being in Double-A, and knowing [the Major Leagues are] still so close in Double-A, I got ahead of myself a lot and that kind of hurt me. So this year I've been taking it real slow and just focusing on one start [at a time]."
With the win, Tacoma improved to 47-33, good enough for first place in the PCL. With a starting rotation that includes Danny Hultzen, James Paxton, Erasmo Ramirez, and Brandon Maurer in addition to Walker, the Rainiers are as well situated on the mound as any team in the Minors.
"I can be Manager of the Year with the staff we have in here now," Stearns joked.