MIAMI -- The Marlins on Saturday night parted with popular and proven closer Sergio Romo to address a need for more offensive firepower in their system.

After Miami lost, 9-2, to the D-backs at Marlins Park, the organization announced Romo was being dealt to the Twins for first-base prospect Lewin Diaz, who will report to Double-A Jacksonville.

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The Marlins also are sending Minor League right-hander Chris Vallimont and a player to be named to complete the deal for the 22-year-old Diaz, who is now ranked by MLB Pipeline as Miami's No. 21 prospect.

“When you think about making trades, we’ve approached this Trade Deadline like we’re not sellers, we’re buyers,” Marlins president of baseball operations Michael Hill said. “We’re trying to add as much talent as we can to this organization. That’s what our goal is -- it’s to add, and continue to add impactful talent to this organization.”

Diaz, 22, is a 6-foot-4, 225-pounder from the Dominican Republic. In 89 combined games at Class A Advanced Fort Myers and Double-A Pensacola, the slugger hit .297 with 19 home runs, 27 doubles and 61 RBIs.

The Marlins consider him an above-average defensive first baseman, with the type of power to hit in the middle of the order.

“From our perspective, we felt like we maximized an expiring asset,” Hill said. “We were able to add, in our opinion, one of the most productive, impactful, left-handed power hitters in all of Minor League baseball in Lewin Diaz.”

Romo, 36, is a free agent after this season. The veteran right-hander, who is making $2.5 million this season, joins a Twins club that is pursuing a playoff berth.

Romo also said he would be open to returning to the Marlins as a free agent after the season.

“First off, I’m extremely grateful for the opportunity to walk in through the doors every day,” Romo said. “Everybody made me feel visible and welcome. I don’t really find that everywhere I go. They let me be myself and I’m super thankful for that.”

Romo has an early flight to Chicago to join the Twins, but will be returning to Miami on Tuesday, when Minnesota is in town for a three-game series.

“We thank Sergio for his time with the Miami Marlins,” Hill said. “We wish him nothing but the best, moving on to the Twins. He did a great job with our young players. Championship pedigree.”

Romo won three World Series rings during his tenure with the Giants. As the Marlins’ closer, he had 17 saves and appeared in 38 games, posting a 3.58 ERA.

The Marlins' closing options include Nick Anderson, but he is drawing interest before Wednesday’s Trade Deadline.

“I’m super excited,” Romo said. “[The Twins are] in a really, really good position to make a playoff push. That’s exciting. It’s super fun baseball to play. But, I kind of have mixed feelings, [because I'm leaving] a bunch of dudes that I’ve grown to love. Cool dudes. I had a good time. They allowed me to be myself. But, here we are. It’s a new chapter.”