SCOTTSDALE, Ariz. -- In an effort to challenge their hitters more this spring, the D-backs, under the direction of hitting coach Darnell Coles, have incorporated some new drills and changed the way they go about others.

During a practice one morning last week, the hitting groups rotated between fields with two focused on situational hitting, one on pitch recognition and one in which hitters moved up closer to the batting-practice pitcher.

"Any time you feel like you have not swung the bats as well as you feel like you should have, you're always trying to make sure you challenge yourself as a hitting group to find ways to get our guys better," Coles said.

The D-backs have a pitching machine that can be programmed to randomly throw balls and strikes, as well as mix up fastballs and breaking balls. The goal is to get hitters out of a routine of only seeing a grooved fastball every time or similar breaking balls.

Having batters move up closer helps them simulate game-speed pitches better, because the coaches who throw batting practice do not throw as hard as Major Leaguers. The closer they are, the faster the pitches look like they're coming in.

"There are also ways to allow us to continue to get better at seeing an arm, seeing it in a structured situation where the batter is closer to the pitcher. So now at 70 mph, batting practice is now 90 mph based on how you’re moving closer to the pitcher," Coles said. "My objective coming in was to make sure that we’re fastball-ready and make our adjustments off that. We’ll be more than prepared once the season starts."

The D-backs plan on using the machines and drills when they can during the regular season as well.

Felt different
When Merrill Kelly got up Monday morning, the D-backs right-hander said he felt like a little kid again as he anticipated his first outing of the spring.

In a two-inning start during Arizona's 7-1 loss to Milwaukee, Kelly allowed two runs on one hit (a home run) and a walk while striking out five. It wasn't just Kelly's first outing of the spring, but it was also his first game action since undergoing thoracic outlet surgery last September.

"It kind of felt like my first Spring Training game back in 2019, just with the butterflies," Kelly said. "With everything that’s been going on and everything that happened last year, it was a lot of fun."

Kelly, who went 3-2 with a 2.59 ERA in five starts for the D-backs last year, hit 92-93 mph with his fastball, which is similar to his velocity from last season.

"Definitely something I was curious about," Kelly said. "From talking to people who have had the procedure I had, some of the feedback from those guys was that it might take a little bit to get back to the velo you were before the surgery. I did take a peek a couple times today. And I did see some [90] 2s and 3s. So being the first time out, being the first game in camp, I'm definitely happy with where it's at right now."

Playing seven-plus
Monday's game went 7 1/2 innings per an agreement reached by D-backs manager Torey Lovullo and Brewers skipper Craig Counsell. For games through March 13, the standard is seven innings, but they can be lengthened to nine or shortened to five, depending on what the managers agree to.

The D-backs and Rockies were going to play one more inning in Sunday's Cactus League opener, but they ended up stopping after eight because Colorado ran out of pitchers.

Roster move
The D-backs outrighted right-hander Keury Mella to Triple-A Reno, but he will be part of Major League camp. Mella, who had a 1.80 ERA in 11 games for Arizona last season, was designated for assignment and removed from the 40-man roster on Feb. 25.

Weeks out
Outfielder Drew Weeks, who was in D-backs camp as a non-roster invitee, will require shoulder surgery and will be out the remainder of the 2021 season.

Up next
The D-backs will host the Padres on Tuesday at 1:10 p.m. MST with left-hander Caleb Smith getting the start. Alex Young, Kevin Ginkel, Miguel Aguilar, Sam Moll and Bradley Roney are also scheduled to pitch for Arizona. Lefty Ryan Weathers will start for San Diego. Listen live on MLB.TV.