PHOENIX -- The D-backs were counting on center fielder Adam Eaton from Day 1 -- Eaton was listed on the NL All-Star ballot, and Gerardo Parra was not.
Three months later, Eaton's opening day is finally here, and he cannot wait to return to what he does best, create a mess for an opponent.
"I like to think I'm a soda bottle that you shake well and you open up," Eaton said of his game.
It was apparent last season, when Eaton showed an ability to apply pressure to a defense during his September callup, and the D-backs believe they will see it again now that he has recovered from a sprained ulnar collateral ligament in his left elbow suffered in spring training.
"He creates a little more havoc," manager Kirk Gibson said. "We can pressure people. That's what he does. He's a irritant. He gets on the bases and makes good plays. He plays the game all out, and he plays it hard. He adds something to our team."
Eaton, 24, made his debut in the leadoff spot against the Los Angeles Dodgers on Tuesday. He was activated after hitting a home run and playing a full game in center field in his one day on a rehab assignment at Class AAA Reno.
Eaton, who hit .259 with two homers and two stolen bases in 22 games with the D-backs last year, has been hitting for three weeks and has been on throwing program for twice as long after suffering a setback that cut short his first rehab assignment in mid-May.
"I felt good," he said. "I felt ready. I told them that. You want to take your time with it. You want to make sure you are right. I think we took the adequate steps to get right.
"It only hurt on one throw, and it felt great ever since. If we can avoid that one throw, we will be fine, and we have so far. We're going to put it out there today. it's going to be fun."
"He is going to probably be conservative," Gibson said. "When he is coming in on the ball, no problem. When he's going side to side, he just has to make sure he gets his mechanics together and throws the ball.
"He's kind of at a point, after he irritated in the second time, where we are going to try to build him up and get him stronger and stronger and stronger. He shouldn't hurt it, but if he does we'll know that he has to have surgery."
Eaton's addition creates a glut in the outfield, giving the D-backs five outfielders, six if you include Martin Prado, who started in left field Monday and was to start there on Tuesday until Eric Chavez was a late scratch with hip stiffness -- moving Prado to third base.
Parra, Eaton, and Jason Kubel hit left-handed; Cody Ross, Pollock and Prado hit right. The depth suggests the D-backs could deal from that area to add to the bullpen at the trading deadline, seemingly their most likely target area.
Eaton will be worked in semi-slowly, Gibson said, similar to the way he used Didi Gregorius when he joined the D-backs off a rehab assignment after an elbow injury on April 18. Eaton is expected to take Wednesday off, when the Dodgers are to start left Hyun-Jin Ryu.
As far as the logjam in the outfield, "I'm not worried about that," Gibson said.
"There is an element that (Eaton) brings that we all saw in spring training before he got hurt. It's time to see if he can withstand the daily grind. Try to get him to that point. Hopefully he is healthy for the rest of the year and can contribute in the way we think he can."
Eaton, too, is not concerned about the roster compostion.
"You have to do out and do your job," he said. "Any of the guys in here will tell you, as soon as you start thinking about that and worrying about that, you are in trouble. If they were to send me back down, it's for the betterment of the team. If they were to need me in September, it's for the betterment of the team."
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