Traded to the Marlins on Dec. 4 for Yunel Escobar, Dietrich now finds himself starting at second base and hitting third.
Injuries to Donovan Solano and Chris Valaika led to Dietrich getting called up from Double-A Jacksonville to Miami on May 8.
Dietrich is making the most of his opportunity. He's hitting .238 with three homers and eight RBIs in 63 at-bats, including an RBI triple in Tuesday's 7-6 loss to the Rays.
"With all of the injuries, he got a chance to come up to the big leagues quicker than any of us anticipated," Miami manager Mike Redmond said. "It's one thing to get the opportunity to come to the big leagues when you're young. It's another to take advantage of that. He's done that."
A year ago, Dietrich was progressing from Class A Charlotte to Double-A Montgomery in Tampa Bay's system.
Naturally, the left-handed hitting infielder felt his future was with the Rays.
This week, Dietrich is getting his first chance to face the Rays in Interleague Play.
"Tampa was obviously my first organization," Dietrich said. "The goal there was to help out the big league team. Now, I'm blessed to have the opportunity to be helping out the Marlins. It is a little weird being in this side of the clubhouse."
Although Dietrich didn't attend big league camp with Tampa Bay, he is familiar with a number of players in the organization.
"It's nice to see those guys," he said. "But once you are on the field it is business as usual.
"The Rays do a great job in raising their players. They really prepare you to be a successful big leaguer. I definitely got better in their organization. I appreciate everything they did for me, giving me that first opportunity. But I'm happy to be here, and be with the Marlins. I couldn't be in a better spot."
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter