Alzolay (side) will begin his season doing rehab work in Arizona and won't join the Triple-A Iowa rotation right away, Tommy Birch of the Des Moines Register reports.
Alzolay has been dealing with a side injury since February, and the Cubs will proceed cautiously with one of their top pitching prospects. Jaron Madison, Chicago's director of player development, said Alzolay is "just a couple of weeks behind" and should be able to join the Iowa rotation in late April or early May.