Speier (1-1, 3.37 ERA) was hit in the shoulder by a line drive from the Padres' Tadahito Iguchi on Sunday. Speier continued in that game, but the shoulder tightened and he hadn't been available in the two games since.
This is the second Major League stint for Newman, who posted a 3.86 ERA and didn't figure in any decisions when he was with the club from April 22 to May 6.
Thomas Harding is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.