"Once they told me what was going on, it definitely put my mind at ease," Shoemaker said prior to Saturday's game against the Rangers. "It's soreness/strain. The timeline is unknown, day to day. Hopefully it'll just be a few days. We're just playing it safe."
Shoemaker, 7-9 with a 4.31 ERA, is having a relatively down year, but he's pitched very well since coming back up from a brief stint in Triple-A. He threw 7 1/3 innings of one-hit ball in Detroit on Aug. 27, then limited the A's to one run in seven innings on Tuesday.
The 28-year-old felt some tightness toward the end of that start in Oakland and woke up the next morning with soreness. But an MRI exam during the off-day on Thursday revealed no structural damage and the Angels can give Shoemaker extra rest by utilizing another off-day this coming Thursday.
"We really don't know until we get through the weekend," pitching coach Mike Butcher said when asked if Shoemaker will miss just one start. "The bottom line is doing what's right for him. It's promising how he feels today. It's not all doom and gloom."
• Collin Cowgill started in left field in place of fellow right-handed hitter Shane Victorino on Saturday, against Rangers lefty Derek Holland. But Victorino wasn't nursing any lingering effects from colliding with the left-field wall on Friday night. Angels manager Mike Scioscia just liked the matchup, with Cowgill homering twice in 10 at-bats against Holland.
• Asked whether Taylor Featherston will continue to start at second base while Johnny Giavotella is out, Scioscia said: "He'll get a chance to play. From the defensive component, there's no doubt he's going to be a positive. … We don't have a guy who's going to swing the bat like Gio right now, so we're going to go with the defensive component."
Alden Gonzalez is a reporter for MLB.com. Follow him on Twitter @Alden_Gonzalez and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.