MESA, Ariz. -- A hardly grizzled Kendall Graveman is just three months removed from his 27th birthday, yet he's unequivocally taken on the role of Oakland's chief of staff.
The surprise factor was subsequently missing when manager Bob Melvin made his Opening Day starter announcement Tuesday.
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"He probably knew a month ago," Melvin quipped.
Graveman doesn't take the assignment for granted, though.
"It's a humbling experience," the right-hander said. "It's something that in this game you strive to be able to do. It's just an honor to be able to go out and kind of set the tone for the season and to be that guy."

"He's ready for it," Melvin said. "He came into camp being ready for it. This is his year to kind of really be the veteran and he's ready for that day, so we're excited about that."
Graveman's second consecutive Opening Day start will be staged in Oakland against the Angels on March 29. His first, also in opposition of the Angels, resulted in a win, with Graveman striking out seven and holding them to two runs and six hits over six innings.
Shoulder injuries, however, limited Graveman to 105 1/3 innings in 2017. He endured two stints on the disabled list -- missing two starts in an otherwise sterling April that saw him pitch to a 2.25 ERA, and nearly three months of starts beginning May 26.
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Health was an ongoing issue for A's starters last year. The injury bug bit early: then-ace Sonny Gray went down with a lat strain in Spring Training, which led to Graveman's initial Opening Day trial. Gray was later traded to the Yankees midsummer, as the A's set out on the path of a rebuild with a group of young players that are hoping to surprise this year.
A powerful lineup has potential to wreak havoc, but there's less certainty within the rotation, further emphasizing the significance of Graveman's work at the top.
"It was unfortunate last year, Sonny getting hurt at the time he did, and it kind of bumped me up to that role, but this year I feel like I'm better prepared to go into it," Graveman said. "It's exciting, but also I've been emphasizing to our starters that our No. 1 is whoever is on the slab that day, whoever's on the bump, and I think we have that mindset with the guys that are going to be out there, that we're going to be really good on the mound."

Melvin is not yet ready to name his other four starters, though the guesswork is minimal at this point. Sean Manaea is a lock, while Daniel Mengden and Paul Blackburn are also strongly favored. That leaves one spot for either Trevor Cahill or Andrew Triggs.
Cahill, whose one-year deal was made official Monday, will make his Cactus League debut on Thursday against the Rockies, with Melvin hoping to get at least two innings out of him, if not more.
"I'm trying to really stress to those guys, look, I might be pitching the first game, but [there are] a lot of games after that," Graveman said. "So I'm excited to see what all of us are going to do this year."