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04/30/2013 11:13 PM ET

Recovering Gregorius cleared for baseball activities

PHOENIX -- Four days after being hit in the helmet with a 93-mph fastball, D-backs shortstop Didi Gregorius cleared all concussion tests Tuesday and resumed normal baseball activities.

"He'll take ground balls, swing and do everything today except play the game," D-backs manager Kirk Gibson said. "He has passed everything he has needed to pass."

Rockies reliever Josh Outman drilled the rookie in the head on Friday and Gregorius complained of soreness and headaches before the D-backs placed him on the seven-day disabled list with a mild concussion. A CT-scan came back normal, but the club opted to err on the side of caution.

Aside from being symptom-free, Gregorius had to pass a series of tests to be cleared that involved answering 20 questions correctly, then exercising under light distress and answering the questions again.

The 23-year-old is eligible to be activated Saturday, but Gibson said he wasn't sure yet whether that will happen on time.

Before the injury, Gregorius had hit safely in all seven games in which he appeared, going 11-for-27 with four doubles and two home runs.

Reynolds feeling strong despite heavier workload

PHOENIX -- Still with a game left to be played in April on Tuesday, D-backs reliever Matt Reynolds has already eclipsed his career-high innings pitched in a single calendar month, tossing 12 2/3 frames over 12 outings this month.

Even with the heavy workload, Reynolds, who has yet to allow a run in 2013 and is riding a 15-inning scoreless streak dating back to last year, said his arm is feeling as strong as ever.

"It feels good," he said. "I prepared for this in the offseason and built my arm strength up for it. Then kind of once the season starts, you do your maintenance on it."

That maintenance is a workout regimen the 28-year-old has developed and tinkered with throughout his career until he felt he had it just right. The type of daily activities he performs includes running, lifting and shoulder strengthening exercises.

"It's become something I've gotten more strict about doing over the years," he said. "I feel like it works and I trust it. It has gotten to the point where I wouldn't be doing anything else anymore."

The results are hard to argue with. The left-hander has walked just one batter this season and is averaging just 12.20 pitches per inning, down from 17.06 from last year. That efficiency has let D-backs manager Kirk Gibson go to Reynolds more often and for a longer duration so far in 2013.

Reynolds pitched two innings or more just three times over his first three seasons in the Majors, all with the Rockies, a feat he's already accomplished twice this year after being acquired in the winter by the D-backs in a trade for Ryan Wheeler.

While Reynolds' success has been a revelation for Arizona thus far, count D-backs closer J.J. Putz as someone who isn't surprised by the southpaw's stats.

"He was impressive when he was on the other side," Putz said. "He throws strikes, he's aggressive, he throws all his pitches for strikes and he's on a pretty good roll right now."

Snake bites

• The D-backs announced Tuesday that they have traded Triple-A Reno utilityman Mark Teahen to the Cincinnati Reds for cash or a player to be named later.

The 31-year-old veteran has hit just .209 with no homers and five RBIs in 21 games with Reno.

• The D-backs signed outfielder Juan Rivera to a Minor League contract on Tuesday. The 12-year veteran was last with the Yankees in Spring Training before being released.

In 109 games with the Dodgers last season, Rivera hit .244 with nine homers and 47 RBIs.

• Aaron Hill, currently on the 15-day disabled list with a broken left hand, had his fractured bone examined Tuesday and the doctors kept him in a splint. The second baseman will be reexamined next week to see how much the bone has regenerated before moving forward with the rehab process.

• Since April 12, Miguel Montero has hit just 8-for-56 and has seen his batting average drop from .265 to .198 over that span. Still, D-backs manager Kirk Gibson is confident the catcher will break out of the slump.

"He hasn't had the results, but he has hit the ball better," Gibson said. "Just like anybody else that is struggling, it takes a life of its own and it becomes more than it should. When you get in a slump, the danger is that you think too much about it. But there's nothing you can do about it, the key is trying to block it out. The good ones do that, he's a good one and so that's what he does."

• In celebration of Dia de los Niños (Children's Day), a handful of Arizona's players hosted and chatted with a group of kids from a local Si Se Puede learning center on Tuesday during batting practice.

The players included Montero, Alfredo Marte, Wil Nieves, Gerardo Parra and Martin Prado.

Earlier in the day, Montero also visited children at the Maricopa Medical Center in Phoenix.

While Children's Day in the U.S. is held in June and isn't as popular as Mother's or Father's Day, in Mexico the holiday is widely celebrated every year on April 30.

Tyler Emerick is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.