Chicago Cubs: Insurance in case of injury
Simply put, having a six-man rotation builds in an insurance policy. It protects a team against a disruptive injury to the starting pitching unit. Should one of the six go down, the Cubs shift gears and revert to the traditional five-man set up. It reduces wear-and-tear on each pitcher, further reducing injury risk. It allows for flexibility through shuffling who starts when should such a need emerge.
Looking beyond 2018, employing a six-man rotation provides some flexibility to work a player like Drew Smyly – who should be fully recovered from 2017 Tommy John surgery – into the mix without having to jettison any of their five starters that will currently be under contract in 2019. Youngsters like Adbert Alzolay and Alex Lange – both looking more-and-more pro-ready – may get a turn without massive disruption to the rotation. It allows for spot starts for the likes of Eddie Butler, Jen-Ho Tseng and yes, even Montgomery.
In terms of insurance, a six-man rotation delivers a smorgasbord of value.