Taijuan Walker not assuming spot in Mariners’ rotation, wants to reach 200 innings

After a promising first full season with the Mariners, Taijuan Walker has one major goal: pitching at least 200 innings.

“Every year I’ve been shut down towards the end but I definitely want to pitch every start and hopefully pitch in the playoffs,” he told “Brock and Salk” on Tuesday.

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Walker, 23, is one of the most promising young pitchers in the game. He put together a solid if not spectacular second half of 2015 before being shut down at 169.2 innings.

While the assumption has been that he’ll be in the Mariners’ rotation, Walker said he feels as though he is competing for one of the final two spots after Felix Hernandez, Hisashi Iwakuma and Wade Miley.

“Nothing is guaranteed,” he said. “We have a lot of great pitchers fighting for two spots so I feel like I’ve still got to stay focused. I’ve got to go out there and compete every game. I can’t take anything off and almost get myself a spot; I have to earn it still.”

After being drafted as a 17-year-old string bean in 2010, Walker said he is up to about 245 pounds. He said the extra weight helps with his power and to get him through the rigors of a full season.

“It definitely helps a lot,” he said. “I work a lot of legs, core and back, and being a pitcher, legs are really important. It’s going to be huge if I want to go six, seven, eight, nine innings, I’m really going to need my legs for it.”

Walker said he primarily stuck to his fastball, slider and hard changeup last season and that he was hurt by the lack of a reliable off-speed pitch. He said he’s been working this offseason on his curveball, which he believes could eventually be a strikeout pitch.

“I think it’s going to be a big pitch for me, just because the speed difference,” he said. ” … I’ve just got to get comfortable with the curveball so I can throw it in any count and eventually it could be a strikeout pitch.”

Beyond the curve, Walker is also picking the brains of pitching coaches Mel Stottlemyre Jr. and Mike Hampton about adding a sinker to his arsenal, “just to show it.”

“Especially if I’m behind in counts, 2-0, 2-1, I can throw a sinker in there and it may hopefully get a ground ball,” he said. “Or even 0-0 if I want a quick out, throw a sinker in there and get ground balls.”