The Phillies announced that Miller will undergo a radiofrequency ablation of the facet joints in his back Friday and is expected to be sidelined 6-to-8 weeks, Paul Casella of MLB.com reports.
Miller might have pushed for a promotion to the majors by now had he been healthy and performing well at Lehigh Valley. However, he's been sidelined all season with nagging back problems, and a decision was made to have the minimally invasive procedure after he visited with multiple spine specialists. The top prospect will rest for one week before beginning the rehab process, and he could be ready to play for Triple-A Lehigh Valley as soon as late July.