"We want to make sure he gets down there and gets consistent at-bats, especially from the left side," manager Joe Maddon said. "We consider him a huge part of our future."
Happ, 24, was a mainstay with the Cubs the past two seasons, highlighted by a 24-home run campaign in his rookie year in 2017. But last season, after a torrid spring followed by Happ hitting the first pitch of the 2018 season for a home run, he struggled to make contact. Happ struck out a whopping 167 times in 387 at-bats. He had 14 strikeouts in 52 at-bats this spring.
"He's not happy," Maddon said. "He shouldn't be happy. He was surprised. I really don't blame him."
Happ platooned mostly in center field with Albert Almora Jr., who is a gold glove candidate. Almora will undoubtedly get more opportunities to start -- as will David Bote, who came on strong in his rookie season last year.
Maddon said the decision by team brass to send Happ down was "unanimous."
"We want the best for Ian, which in turn is the best for us also," the manager said.
Happ has a respectable career .801 OPS, as he did walk 70 times in 2018, but only two hitters in baseball had worse strikeout rates. In fact, according to ESPN Stats & Information, his 2017 and 2018 seasons feature the worst two strikeout rates by a player in a single season in Cubs history (min. 400 PA).
Maddon said that it's always tough to send down an established player, but it's not like releasing one -- with that, his dreams are completely shattered. If Happ responds the right way -- by making more contact -- he'll be back soon enough.
"With a young player, they are never going to quite understand it or want to do it," Maddon said of going to the minors. "We knew it would be a difficult conversation, but having difficult conversations should never dissuade you from making what you perceived to be the right decisions."
Happ's place on the roster now falls to outfielder Mark Zagunis.
Maddon also said the team is having "great discussions" about looming bullpen decisions. The Cubs granted righty Junichi Tazawa his release on Saturday and sent right-handers Alec Mills and Dillon Maples to Triple-A.