The Reds announced Monday that infielder/outfielder Derek Dietrich, infielder Christian Colon, right-hander Jackson Stephens and right-hander Keury Mella all went unclaimed on waivers and were set outright to Triple Louisville.

Dietrich, 30, is the most notable name of the group and will surely reject the assignment to once again become a free agent. The former Marlin parlayed a minor league deal in Cincinnati this offseason into an Opening Day roster spot and went on one of the more memorable power surges in recent memory midway through the year. Dietrich launched a dozen homers over a span of just 68 plate appearances in May and carried a 1.000 OPS into June. However, he fell into a slump that was perhaps even more remarkable than that home-run binge; in his final 71 plate appearances, he hit just .071/.257/.179.

Mella, 26, was acquired from the Giants alongside Adam Duvall in the 2015 trade that shipped righty Mike Leake to the Giants. He was considered to be among the more promising pitching prospects in Cincinnati in the couple of years following that trade but has seen his stock dip considerably. The righty yielded 15 runs in 17 Major League innings across parts of three seasons, posting an uninspiring 13-to-12 K/BB ratio during those stints. At the time of his acquisition, Mella was averaging better than a strikeout per inning against older competition in Class-A Advanced, but in parts of three Triple-A seasons he has a 4.59 ERA with 6.4 K/9 against 3.3 BB/9 in 172 2/3 innings.

The 25-year-old Stephens had a big year with Double-A Pensacola back in 2016 but has limped to an ERA north of 5.00 in three trips through Triple-A Louisville while struggling to a 4.83 ERA through multiple MLB auditions. He spent the 2019 season in Triple-A, where he logged a 5.14 ERA with an 80-to-37 K/BB ratio in 84 innings, mostly as a reliever.

Colon, once the fourth overall pick in the draft and a top prospect with the Royals, appeared in just eight games with the Reds and made eight plate appearances. He’s a career .256/.321/.218 hitter in the Majors and batted .300/.372/.443 in Triple-A with the Reds this past season.