January 05, 2021

Diamondbacks  sign Seth Frankoff as a free agent

January 18, 2021

Diamondbacks  sign Bryan Holaday

Diamondbacks  sign Ryan Buchter

February 06, 2021

Diamondbacks  sign Joakim Soria as a free agent

February 09, 2021

Diamondbacks  sign Matt Gage

February 11, 2021

Diamondbacks  sign Christian Lopes

Diamondbacks  sign Chris Devenski

February 21, 2021

Diamondbacks  place Luis Frias on the injured list

February 22, 2021

Diamondbacks  sign Asdrubal Cabrera as a free agent

February 26, 2021

Diamondbacks  designate Travis Bergen for assignment

Diamondbacks  designate Keury Mella for assignment

Diamondbacks  designate Luis Frias for assignment

Diamondbacks  sign Tyler Clippard as a free agent

February 28, 2021

Travis Bergen traded from Diamondbacks  to Blue Jays 

March 04, 2021

Diamondbacks  sign Anthony Swarzak as a free agent

March 19, 2021

Diamondbacks  sign Stone Garrett as a free agent

March 27, 2021

Diamondbacks  sign Bryan Holaday as a free agent

March 29, 2021

Diamondbacks  place Tyler Clippard on the injured list

April 01, 2021

Diamondbacks  place Zac Gallen on the injured list

Diamondbacks  place Kole Calhoun on the injured list

April 03, 2021

Diamondbacks  place Nick Ahmed on the injured list

April 06, 2021

Diamondbacks  place Joakim Soria on the injured list

April 08, 2021

Diamondbacks  place Ketel Marte on the injured list

April 12, 2021

Diamondbacks  place Christian Walker on the injured list

Diamondbacks  sign Josh Reddick as a free agent

April 17, 2021

Diamondbacks  designate Jeremy Beasley for assignment

Nick Heath traded from Royals  to Diamondbacks 

April 18, 2021

Diamondbacks  place Tim Locastro on the injured list

Diamondbacks  designate Anthony Swarzak for assignment

April 22, 2021

Jeremy Beasley traded from Diamondbacks  to Blue Jays 

April 23, 2021

Diamondbacks  release Anthony Swarzak

April 28, 2021

Diamondbacks  place Taylor Widener on the injured list

Diamondbacks  place Kole Calhoun on the injured list

May 04, 2021

Diamondbacks  place Merrill Kelly on the injured list

May 11, 2021

Trayce Thompson traded from Diamondbacks  to Cubs 

May 12, 2021

Diamondbacks  place Zac Gallen on the injured list

Diamondbacks  place Christian Walker on the injured list

Diamondbacks  designate Wyatt Mathisen for assignment

May 14, 2021

Diamondbacks  place Asdrubal Cabrera on the injured list

May 15, 2021

Diamondbacks  place Kole Calhoun on the injured list

Diamondbacks  place J.B. Bukauskas on the injured list

Diamondbacks  place Carson Kelly on the injured list

Diamondbacks  place Chris Devenski on the injured list

May 16, 2021

Wyatt Mathisen traded from Diamondbacks  to Rays 

May 18, 2021

Diamondbacks  place Luke Weaver on the injured list

May 19, 2021

Diamondbacks  sign Henry Ramos

May 20, 2021

Diamondbacks  designate Yoan Lopez for assignment

May 22, 2021

Yoan Lopez traded from Diamondbacks  to Braves 

Diamondbacks  sign Noe Ramirez

May 25, 2021

Diamondbacks  place Taylor Widener on the injured list

May 27, 2021

Diamondbacks  place Luke Weaver on the injured list

June 02, 2021

Diamondbacks  designate Domingo Leyba for assignment

Ildemaro Vargas traded from Pirates  to Diamondbacks 

June 03, 2021

Diamondbacks  place Madison Bumgarner on the injured list

June 04, 2021

Diamondbacks  place Seth Frankoff on the injured list

June 14, 2021

Diamondbacks  place Jon Duplantier on the injured list

June 15, 2021

Diamondbacks  place Seth Frankoff on the injured list

Diamondbacks  place Taylor Clarke on the injured list

June 18, 2021

Diamondbacks  designate Keury Mella for assignment

June 19, 2021

Diamondbacks  designate Ildemaro Vargas for assignment

Diamondbacks  sign Jake Faria as a free agent

June 20, 2021

Diamondbacks  place Carson Kelly on the injured list

June 23, 2021

Diamondbacks  designate Stefan Crichton for assignment

June 28, 2021

Diamondbacks  place Ketel Marte on the injured list

July 01, 2021

Tim Locastro traded from Diamondbacks  to Yankees 

July 02, 2021

Sam Moll traded from Diamondbacks  to Athletics 

July 03, 2021

Diamondbacks  place Zac Gallen on the injured list

July 05, 2021

Diamondbacks  designate Ryan Buchter for assignment

July 10, 2021

Diamondbacks  place Asdrubal Cabrera on the injured list

Diamondbacks  designate Nick Heath for assignment

July 16, 2021

Stephen Vogt traded from Diamondbacks  to Braves 

July 21, 2021

Diamondbacks  designate Alex Young for assignment

July 24, 2021

Diamondbacks  place Josh Rojas on the injured list

July 27, 2021

Diamondbacks  release Jon Duplantier

July 28, 2021

Diamondbacks  release Keury Mella

July 30, 2021

Diamondbacks  place Noe Ramirez on the injured list

Diamondbacks  place Pavin Smith on the injured list

Diamondbacks  place Joe Mantiply on the injured list

Diamondbacks  place Stuart Fairchild on the injured list

Diamondbacks  place Riley Smith on the injured list

Joakim Soria traded from Diamondbacks  to Blue Jays 

July 31, 2021

Diamondbacks  sign Jon Duplantier

August 05, 2021

Diamondbacks  designate Josh Reddick for assignment

August 07, 2021

Diamondbacks  release Josh Reddick

August 12, 2021

Diamondbacks  place Kole Calhoun on the injured list

Diamondbacks  place Taylor Widener on the injured list

August 15, 2021

Diamondbacks  place Merrill Kelly on the injured list

Diamondbacks  place Joe Mantiply on the injured list

August 29, 2021

Diamondbacks  release Bryan Holaday

September 07, 2021

Diamondbacks  place Tyler Clippard on the injured list

September 08, 2021

Diamondbacks  release Seth Frankoff

September 15, 2021

Diamondbacks  place Tyler Gilbert on the injured list

September 17, 2021

Diamondbacks  place Seth Beer on the injured list

September 19, 2021

Diamondbacks  designate Jake Faria for assignment

September 21, 2021

Diamondbacks  place Seth Beer on the injured list

September 26, 2021

Diamondbacks  place Nick Ahmed on the injured list

October 08, 2021

Chris Devenski became a free agent

October 25, 2021

Diamondbacks  sign Chris Devenski

November 04, 2021

Tyler Clippard became a free agent

Kole Calhoun became a free agent

November 26, 2021

Diamondbacks  designate Brett de Geus for assignment

Jordan Luplow traded from Rays  to Diamondbacks 

November 29, 2021

Diamondbacks  sign Braden Bishop

November 30, 2021

Taylor Clarke became a free agent

December 01, 2021

Diamondbacks  sign Mark Melancon as a free agent