BALTIMORE -- Injured second baseman Brian Roberts has been participating in light baseball activities at the team's Minor League Complex in Sarasota, Fla., according to interim manager Juan Samuel.

"What that means, there's no description to it, but he just added very light [baseball activities]," Samuel said Saturday. "That's what my report says."

Roberts had been resting from the third epidural injection in his lower back, and the second baseman told Samuel on June 15 that he was four to six weeks away from returning, with the exact time frame dictated by when he returned to baseball-related activities.

Roberts has been on the 60-day disabled list (herniated disc in his lower back) since April 10, and at this point he isn't expected back until August at the earliest.

Although Roberts hasn't played in a game since the home opener on April 9, the Orioles second baseman has remained steadfast in his belief that he will see the field at some point this season. He has said previously that he has not considered having season-ending surgery.

Wigginton rests back against Nats

BALTIMORE -- Ty Wigginton was out of the Orioles' starting lineup for Saturday's 6-5 victory over the Nats, but interim manager Juan Samuel said he was just being safe in giving the slugger an extra day off to rest his sore back.

"He did not feel 100 percent yet, so we are being cautious, giving him an extra day," Samuel said. "I think he could use another off-day anyway. He's been the one that has been out there every day. We're just being a little cautious with him."

Saturday was just the third time since April 13 that Wigginton was not in the starting lineup, but unlike Friday, he was available to pinch-hit. He went to the plate in the seventh inning of a tie game with two outs and runners on the corners. He was walked intentionally after the O's scored a go-ahead run on a wild pitch during his at-bat, and stayed on to play first base.

While Samuel expects Wigginton to be in the starting lineup Sunday, if he's not, the situation could be a growing concern. But Wigginton doesn't believe that the back stiffness will become a nagging injury.

"It was never to the point where I was overly worried about it," he said.

He has been one of the Orioles' most productive hitters this season, with a .270 average and team highs of 40 RBIs and 13 homers. But he's struggled in the last month, hitting .223 with nine RBIs and no home runs since May 23. Wigginton said he doesn't think pitchers are avoiding him after his hot start, but rather are just doing a better job of keeping the ball down against him.

"The whole key is when you get that mistake, not missing it," he said. "There's been a few times here lately where I have fouled it off. ... It's not like you're a marked man. I wouldn't say that. ... You've got to be even more disciplined, take your walks and find a way to get on base."

O's want Pie to play field before returning

BALTIMORE -- In order to return to the Orioles for their road trip beginning July 2, outfielder Felix Pie will need to play in the outfield and get comfortable with his throwing during his Minor League rehab assignment.

"There's been some discussion whether he's going to go with us on the road trip or not. We'll see how he continues his rehab assignment," interim manager Juan Samuel said. "We would like to see him play the outfield at least three or four games and throw some more."

Pie, on the disabled list since April 16 with an upper back strain, has gone 3-for-7 in two games as the designated hitter for Class A Advanced Frederick. Samuel said that Pie will stay in Frederick for two or three more days before continuing his rehab assignment with Double-A Bowie. He also played two games in the Gulf Coast League.

"He's been swinging for a while, and he played long toss yesterday, which was good," said Samuel, who mentioned that the team's trainers have been cautious with letting Pie throw. "We'd like to see him probably at some point take some infield or throw to the bases. That's something that will probably tell us if he's ready to step in and play left field right away."

Worth noting

Manager Juan Samuel said that Scott Moore, who started at first base in Wigginton's absence, feels more comfortable at the corner than he did at second base. While playing second base, Moore was thinking too much about his at-bats and made some defensive mistakes, according to Samuel.