The Oakland Athletics placed right-hander Joe Boyle (back) on the 15-day injured list on Monday with a lower-back strain and recalled left-hander Hogan Harris from Triple-A Las Vegas in a corresponding move. Boyle heads to the shelf a day after giving up four runs while walking three in an inning to take his fifth loss of the season on Sunday versus the Miami Marlins. The poor outing dropped the 24-year-old to 2-5 on the year with a 7.16 ERA (5.07 FIP) and 1.73 WHIP with a league-leading 23 walks and 29 strikeouts in 27 2/3 innings over his first seven starts. It's unclear who will replace Boyle in Oakland's starting rotation, but it could be Mitch Spence after he tossed 4 2/3 innings in relief of Boyle on Sunday after he left with his back injury.

Oakland Athletics manager Mark Kotsay told right-hander Joe Boyle that he will be the team's fifth starter to open the season behind Alex Wood, Ross Stripling, JP Sears and Paul Blackburn. Boyle will throw in Arizona against Double-A hitters on Wednesday as his final tune-up before making just his fourth major-league start. In his first three MLB starts with Oakland last year, Boyle allowed just four runs (three earned) on eight hits (one homer) while walking five and striking out 15 in 16 innings pitched. The 24-year-old has a history of wildness, though, as evidenced by his 15 walks in 18 1/3 Cactus League innings this spring. The 6-foot-7 hurler throws gas but will need to command it in order to have success and remain in Oakland's rotation for the long haul. At best, he's a waiver-wire pickup in AL-only leagues.