Merrill Kelly returns as Diamondbacks move key starter into relief role

BALTIMORE — The Arizona Diamondbacks retooled their pitching staff on the eve of the second game of their three-game set with the Baltimore Orioles, reinstating right-hander Merrill Kelly to start Tuesday while shifting a rotation mainstay to the bullpen.

With six starters on hand, manager Torey Lovullo opted to move right-hander Brandon Pfaadt into a relief role, replacing Tayler Rashi in the relief corps. Rashi was optioned to Triple-A Reno in the corresponding roster shuffle.

Pfaadt had anchored the rotation for the past three seasons, but a string of uneven outings prompted the change. Through 16.2 innings this season, he owns a 5.94 ERA—the highest among the club’s five starters—and a 1.38 WHIP, second-worst in that group. His tendency to surrender crooked numbers in single frames has undercut otherwise promising strikeout totals.

Lovullo framed the move as a developmental opportunity, saying the organization believes shorter, high-leverage stints will allow Pfaadt to refine his swing-and-miss arsenal while providing immediate help to a bullpen that showed cracks in Monday’s series-opening loss to the Orioles.

By keeping Pfaadt on the active roster rather than sending him to Reno, Arizona retains flexibility and gains a fresh power arm capable of limiting damage per inning. The club is betting that targeted usage will produce more consistent results from the 25-year-old.

Kelly’s activation completes the staff shuffle and restores clarity to the rotation. The veteran right-hander, sidelined since early April with a shoulder issue, will take the ball Tuesday night at Camden Yards as the Diamondbacks look to even the series.