BALTIMORE -- There were times during Spring Training when manager Buck Showalter wasn't sure Jim Johnson would be the closer the Orioles needed him to be at the start of the season.

Johnson had been struggling with a lower back strain that kept him out of games for the first half of the team's camp. His velocity was down as much as five mph, and the righty said it felt like he was throwing "underwater."

"I went through some periods in the spring where I was kind of going, 'Boy, I don't know if he's going to quite get there,'" Showalter said. "We went through a long period there with him where we were really being cautious with him."

But Showalter said there was an outing towards the end of spring where Johnson showed he was 100 percent, and he could see it on the closer's face.

Any concerns about Johnson's health are in the past, as he's established himself as one of the game's premier closers by posting a Major League-best 15 saves and pitching to a 0.92 ERA.

Dating back to last season, Johnson has converted 23 consecutive save opportunities.

"Jimmy never cheated the process," Showalter said. "That's why he is getting a return."

Johnson has been far from the typical closer, as he's used his sinker to get ground balls rather than trying to strike every batter out.

"When you go out and close one-run games facing the [Nos.] 2-3-4 of a tough lineup in the American League East on the road, that's a difference maker," Showalter said.

Roberts to start rehab assignment Wednesday

BALTIMORE -- Brian Roberts, who hasn't played in a Major League game in more than a year, will begin a rehab assignment with Double-A Bowie on Wednesday. The news, while a huge lift of optimism for an organization that has played the better part of three years without their longest-tenured player, isn't a shock given Roberts' recent comments.

"We wanted to get through one more day," Roberts said of the timing of Tuesday's announcement, which was first made by manager Buck Showalter on the Mid-Atlantic Sports Network pregame show.

"We had this kind of tentatively scheduled for a while, but the more people know about it -- obviously -- the more pressure there is. If for some reason we needed an extra day or two, we didn't want to deal with the questions and repercussions as to why."

There have been many questions surrounding Roberts, who has admitted numerous times during his concussion recovery that he thought he had reached the end of the road in terms of his baseball playing days. Asked Tuesday if he felt a return to a dynamic leadoff hitter and All-Star second baseman was even possible at this point, the 31-year-old preached patience.

"Standing here today, I can't say that I'm going to be Brian Roberts tomorrow," he said. "I'm not going to go out there and probably be running into walls tomorrow. But I am going to be out there, and it's going to be a progression. And I hope by the time I rejoin our Major League team I will be the same guy I was five years ago. [It] doesn't mean you don't make some minor adjustments here and there. I want to be on the field and helping this team, whatever that looks like."

The plan is for Roberts to play second base for a few innings and get several at-bats on Wednesday and he will start out playing second base the first few games, although that plan is tentative and could also include some time at designated hitter. Roberts, who hasn't played in the big leagues since May 16, 2011, expressed gratitude for all those who have aided his road to recovery -- including Minnesota's Justin Morneau, who he spoke with Tuesday morning -- and admitted there will be a mixture of joy and apprehension when he takes the field.

"[I'm] excited, scared, a little bit of everything," Roberts said of his return. "It's been a long time coming for sure."

Per Major League Baseball's rules for position players on rehab assignment, Roberts will have 20 days to get himself ready to rejoin the Orioles, a time period he is expected to maximize.

"I'm pretty sure we will use the 20," Roberts said. "It's been over a year and I need to get some at-bats. I stood in on some bullpen sessions and it looks pretty fast. I need to get in there and see some pitches. The first week, it's probably only going to be two or three at-bats a day. So it's going to take a little while to build up. ... We are going to use as much time as we can."

Since joining O's, Strop overpowering batters

BALTIMORE -- For two and a half years while he was with the Rangers, Pedro Strop felt like he was constantly looking over his shoulder.

Strop said he put a lot of pressure on himself as he struggled to stay with the big league club, and the results showed in his performance. In 27 1/3 innings with Texas, Strop posted a 7.24 ERA.

That all changed when Strop was claimed off waivers by the Orioles on Sept. 1 and thrown into a game against the Rays only two days later. Finally, a team had confidence in Strop, and that gave Strop confidence in himself.

"They were using me in really important situations in a game, and when you see that, you figure that if you get involved in those kind of situations, it's because they trust you," Strop said. "After that, that's when everything came [together]."

Strop has been nothing short of dominant since joining the O's, pitching to a 1.00 ERA in 36 innings thanks to a refined delivery and the increased use of his two-seam fastball.

So far in 2012, Strop has been Baltimore's primary setup man. He's also earned three saves when regular closer Jim Johnson was unavailable.

"He's really been a weapon for us early on," manager Buck Showalter said. "He's got a lot of ways to get you out."

Strop said the key to his turnaround has been the use of the two-seamer, which he's thrown on more than 50 percent of his pitches this season after using it only sparingly with the Rangers.

After battling soreness and arm fatigue, which were hurting his velocity, Strop switched to the two-seamer upon his arrival in Baltimore. He also adjusted his mechanics, ditching what was an almost sidearm delivery in favor of getting more on top of the ball.

As a result, Strop said his arm feels fresher and he's been inducing more ground balls. He's also throwing his fastball harder, with an average velocity of almost 97 mph this season.

"I used to strike out a lot of people, but now I just want to get rid of hitters as soon as possible," Strop said. "The season is long. You've got to be able to be available as much as possible to help the team."

Showalter was quick to point out that Strop still has a lot of room to grow. The 26-year-old righty needs to learn to control his emotions and pitch with his over-the-top delivery more consistently.

"It's a work in progress. I don't think we've seen enough to really know exactly what he's going to do over the long haul," Showalter said. "It's not so much not knowing the physical things he's doing, it's being able to keep the emotions in check enough to be able to do that physically. So I think that's what he fights sometimes. He's got so much want-to and so much emotion, the last thing I want to do is take that away from him. I want him to be who he is."

Tidbits

• The Orioles are discussing a promotion for top pitching prospect Dylan Bundy, which looks like a near-certainty at this point. Bundy, who hasn't allowed an earned run, isn't expected to skip a level and will likely head to Class A Advanced Frederick.

• Third baseman Mark Reynolds appears to be nearing a return, as he hit off coaches while rehabbing his strained left oblique in Sarasota, Fla., on Tuesday. Endy Chavez, also in Sarasota rehabbing the same injury, remains a step behind Reynolds and was limited to soft toss and hitting off a tee.

• Nolan Reimold (herniated disk) is scheduled to get his second epidural injection on Friday. Since the first epidural didn't work, Reimold could need a third shot and it's impossible to target any timetable for his return at this point.

• Pitcher Tsuyoshi Wada arrived at the team's facility in Sarasota on Tuesday to begin the next phase of his rehab from Tommy John surgery. Wada had the surgery in Los Angeles on May 11 and had previously been rehabbing there.

• Catcher Taylor Teagarden's appointment to get a second opinion on his back injury is scheduled for Thursday at 3 p.m. ET. Teagarden has been on the disabled list since Spring Training started.