Bieber (elbow) will throw off a mound Saturday, Mitch Bannon of The Athletic reports.
It will mark the first time Bieber will throw off a mound this season, as the right-hander had been limited to flat-ground work during spring training. Bieber obviously has several more hurdles to clear before he's making starts for the Blue Jays, as he needs to build his arm up and will likely require multiple rehab starts. There's a chance Bieber will be ready to pitch for Toronto sometime in May.