PHOENIX -- Exactly two weeks after an MRI revealed a UCL sprain in his left elbow, D-backs rookie outfielder Adam Eaton will begin swinging in the batting cage on Thursday, the first step in his return to game action.
Eaton, the D-backs' No. 5 prospect according to MLB.com, will hit off a tee and have balls flipped to him at the team's Spring Training facility in Scottsdale while the club travels to Milwaukee for its first road trip of the season.
"I know he's excited to do that," D-backs manager Kirk Gibson said. "He's really champing at the bit."
While swinging the bat is progress, Eaton is still at least two weeks away from throwing a ball again. The injury didn't require surgery, but the initial prognosis called for him to be shut down for a month.
In the meantime, Eaton could rack up at-bats in extended Spring Training games while his elbow continues to heal before eventually starting a rehab assignment somewhere in the D-backs' farm system.
The club's timetable has the outfielder on a path to be back with the D-backs around early to mid-May.
Eaton was slated to take over center field for the D-backs after they traded away Chris Young in the offseason. The 24-year-old hit .390 this spring, with 23 hits and 10 RBIs in 59 at-bats.
Sipp feeling good about new surroundings after debut
PHOENIX -- Even though his first outing in a D-backs uniform lasted only a few moments in Tuesday's 6-1 loss against the Cardinals, Tony Sipp was pleased to get the first one under his belt after spending the first four years of his Major League career with the Indians.
With two runners on base and two outs in the sixth inning, D-backs manager Kirk Gibson called on the southpaw to retire the left-handed-hitting Daniel Descalso and get the club out of the jam. Sipp admitted he felt nervous on his way from the bullpen to the mound, but those butterflies soon flew away as he needed just one pitch to retire the Cardinals batter and end the inning.
"It was kind of over before I even realized it," he said. "I didn't think it'd be that quick. It felt good though to have good results. Obviously, there are a lot more outings left and not all of them will be that easy, but just to even get out there and get the jitters out of the way felt nice."
The pitch Sipp got Descalso out on was a 76-mph slider up in the zone that induced a fly ball to center.
"We knew he was going to be aggressive in that situation, so we threw a breaking ball and got him out in front," Gibson said. "That's the kind of bullpen change you like to make."
The D-backs acquired Sipp this winter in a trade that involved Trevor Bauer going to Cleveland and Arizona netting Didi Gregorius. When the left-hander first became aware of the move, he was worried about adjusting to a new organization, but since arriving this spring, the transition has been as smooth as possible.
"It has gone way better than I expected it to, I thought it might be awkward at first, but I haven't had an awkward day," Sipp said. "From day one, I came in and it felt like everyone really guided me through and showed me the ropes. They've done an amazing job of helping me if I forget a name or if I need to know where to go. I've really enjoyed it because if everyone is joking around and laughing, it makes it easier for the new guy to come in and feel comfortable."
The biggest difference between the Indians and his new club, Sipp said, is how much the D-backs' coaching staff works to develop the fundamentals like holding runners on base.
"They really drill it, but it's not like it's tedious," he said. "They make sure you're doing things right and I don't mind it at all because it only helps you in the game."
In 249 career appearances, Sipp has a 3.67 ERA and 225 strikeouts and 111 walks.
• A day before leaving Phoenix to begin their rehab assignments, injured Arizona players Didi Gregorius (right elbow) and Cody Ross (left calf) worked out on the diamond at Chase Field on Wednesday.
Ross ran the bases and worked on slides while Gregorius took ground balls and threw across the diamond to first base. Ross will head to Class A Advanced Visalia and Gregorius will go to Triple-A Reno. Both players are expected to pinch-hit and DH before playing in the field.
• As the only D-backs reliever not to appear in a game entering Wednesday's series finale against the Cardinals, J.J. Putz will most likely throw the ninth inning no matter what the score is, according to Gibson.
• Wade Miley and Patrick Corbin each threw bullpen sessions on Wednesday and are ahead of their scheduled season debuts in Milwaukee on Friday and Saturday, respectively.
• With three off-days coming in the next 12 days, Gibson has no plans to give catcher Miguel Montero a day off.
"He caught 136 games last year and he wants to catch more this year," Gibson said. "He's an elite catcher and a day off now is not going to matter in August when it's hot out and we're traveling all over."
Tyler Emerick is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.