Lopez will return to starting in 2018, Tom Haudricourt of the Milwaukee Journal Sentinel reports.
Lopez had moved from the rotation to the bullpen last season at Double-A Biloxi, finishing the year with 13 starts and a further 26 appearances out of the pen. He spent the winter starting games in the Dominican Winter League. The 25-year-old has made brief appearances at the big-league level in two of the last three seasons, starting two games in 2015 and appearing once out of the bullpen last season.