"We knew it would take a few more days before [Qualls would] be able to go out and compete, so we felt like we needed to make a move," Rockies manager Walt Weiss said. "Oberg is throwing the ball really well. We're looking forward to seeing Scotty out there."
Oberg has had mixed results in two stints with the Rockies this season. In his first stint, he allowed six runs in 11 1/3 innings and was optioned to Albuquerque after allowing five runs in his last two outings. He only made one appearance in a short-lived second trip to the Majors, throwing two scoreless innings in Miami.
However, Oberg has been successful in Albuquerque as the Isotopes' closer. He has a 2.43 ERA with nine saves in 22 appearances and uses four different pitches, which is rare for a reliever.
"He's got plus stuff across the board, it's just a matter of commanding it, and that's what he's doing," Weiss said. "His fastball is very lively. We think a lot of the kid. I certainly do, and he's throwing the ball very well."
Oberg could be used in several different roles, including as an emergency closer. He has not thrown more than two innings in an outing in the Majors or Minors this season, although five of his 10 outings in the Majors have been two innings.
Oberg pitched a scoreless seventh inning Saturday night in his first appearance since being recalled.
• Right-hander Justin Miller threw his first simulated game since being placed on the 15-day DL on July 5 with a left oblique strain. He threw to outfielders Brandon Barnes and Gerardo Parra and infielder Cristhian Adames.
"I was just trying to throw everything with max effort and throw strikes," Miller said. "When you're throwing [side sessions], you don't have anybody standing in the box, so it's good to have somebody there to get that feel."
Miller is expected to go on a rehab stint in Albuquerque on Monday, when the Rockies open a three-game series in Baltimore.
• Parra (left ankle sprain) is planning on running before each game in Baltimore. If he is healthy enough, he'll go on a rehab assignment after that.
Parra said he felt tightness but no pain in the ankle when he tried running during this homestand. He was able to take batting practice after hitting in Miller's simulated game.