It was not immediately known when or whether Butler, 25, a supplemental first-round choice out of Radford University in 2012, would be added to the starting rotation. Butler is 2-0 with a 4.09 ERA in four starts at Albuquerque. He has gone six innings in each of his last three starts, with a 3.00 ERA, 10 strikeouts and three walks.
In Major League stints the last two years, Butler is a combined 4-11 with a 6.04 ERA in 19 starts. Last year, he made the Opening Day roster and went 3-10 with a 5.90 ERA in 16 starts over two stints.