Jakubauskas left in the first inning after Lance Berkman's line drive hit him in the head, behind his right ear. He was carted off the field and taken to a nearby hospital, where he was kept overnight for observation.
Jakubauskas told Pittsburgh manager John Russell on Sunday that he was feeling better and that the dizziness he experienced on Saturday night had subsided.
"He's doing pretty good," Russell said. "He's feeling OK, a little tired obviously. We were fortunate. It could've been a lot worse. It's looking like it's working out pretty good for him. He was in pretty good spirits."
Russell was awaiting word whether Jakubauskas would be able to fly with the team to Milwaukee, where the Pirates open a three-game series on Monday. Jakubauskas was not at the ballpark before Sunday's game.
"If he starts getting dizzy at some point today, we'll make other arrangements," Russell said. "But so far, so good."
Jakubauskas' injury forced Russell to use five relievers in Saturday's 5-2 loss. Burres had just been optioned to the minors on Wednesday. He appeared in two games for Pittsburgh between April 12-21, including one start.
Bass spent the 2009 season with Baltimore and finished second among AL relievers in innings pitched (86 1-3). He was 0-1 with a 4.05 ERA in four appearances with Indianapolis this season.
"It gives us two guys who are capable of pitching long," Russell said. "Just gives us options for multiple innings, but also guys who can do a good job for us. The main thing is the bullpen is pretty taxed. We've got to make sure we've got some coverage."
Russell said Burres or Bass could start in Los Angeles on Thursday.