MESA, Ariz. (AP) – A grinning Billy Butler strolled into Oakland’s spring training clubhouse early Saturday, a bright green Athletics duffel bag draped over his right shoulder to match his upbeat mood, then walked right up to pitcher Jesse Hahn and offered a fist bump.

“I’m an early guy, man,” Butler declared.

Indeed, he was among the first players to show up at Hohokam Stadium on a day only pitchers and catchers were due at the ballpark to check in for physicals ahead of the club’s first workout Sunday. And Butler means business after a disappointing first season with the A’s during which the veteran designated hitter batted .251 with 15 home runs and 65 RBIs.

The 29-year-old Butler is confident his intense regimen all winter in Arizona will only benefit him early in spring after he was limited last year at this time because of wrist injuries that didn’t allow him to swing a bat right away.

“We’ve got a long way to go,” Butler said. “It’s Feb. 20. I’m ready to get started.”

This offseason, he would work out with a trainer in the mornings then go to the A’s complex to hit afterward. On Saturday, he spent time studying film in a quiet room off the clubhouse.

“Especially when you come to a new team and you have a year that you don’t feel like went right, you spend a good portion of your offseason taking a long look at how you can do things better, and he has a track record of hitting,” manager Bob Melvin said Saturday. “I know he’d like to put last year in the rear-view mirror.”

Even with a strong September, Butler hardly left the kind of first impression he had hoped for following his departure from the Kansas City Royals and the only team he’d known for eight years.

“You can’t really explain why things happen. It wasn’t the year I wanted,” he said. “You get a new year, you get a new start, you get a new opportunity.”

For an Oakland team that finished last in the AL West at 68-94 after three straight playoff berths, seeing Butler bounce back in 2016 would provide quite a boost.

“He’s got a good attitude coming in. From his expectations he didn’t have the year he wanted to last year, but you look back at his full season and it definitely wasn’t an awful year,” ace Sonny Gray said. “He’s going to potentially be a really big part of this team if we’re going to go where we want to go. He’s going to be a guy we’re going to have to rely on. Hopefully he comes out this year and performs well – there’s no doubt in my mind he will.”

The 26-year-old Gray also will take on a key role in any turnaround by the A’s. The right-hander won 14 games each of the past two seasons and has quickly become one of the faces of the franchise.

Gray plans to consume more calories to try to keep his weight closer to 185 after pitching at 178-180 last season. He was 205 while in college at Vanderbilt.

Butler has faced weighty questions of his own for more than a decade – and he gets it.

“I am in good shape, I’m strong, my body’s where I need to be. I’m going to perform to the level they expect me to,” he said. “I’ve always had a bigger body type, even when I was 18. I wasn’t going to be drafted to steal bases at 18. The questions don’t happen when you hit 30 homers, right? If you hit 30 home runs, you hit 40 doubles, I don’t think anybody questions your conditioning or your offseason program. … I’ve got a lot left in the tank.”

That means doing all the extra work.

“I’m getting older, I think I’ve got to do more things to stay young – to stay younger,” he said. “I’m not old, I’m old in baseball terms. It’s one of those things you’ve got to do more to keep up with these young bucks.”

His teammates have few concerns.

Catcher Stephen Vogt texted with Butler throughout the offseason and received regular messages from the DH saying, “Hey, I’m ready for this year.”

“He’s one of the best hitters in baseball,” Vogt said. “His track record speaks for itself. I don’t think one year where he wasn’t satisfied … he’s going to bounce back. I have confidence he’s going to come back and have a great year for us.”