| 06/26/19 | Detroit Tigers optioned 3B Dawel Lugo to Toledo Mud Hens. |
| 06/25/19 | New York Yankees optioned RHP Jonathan Holder to Scranton/Wilkes-Barre RailRiders. |
| New York Yankees signed RHP Nelson Alvarez. | |
| Baltimore Orioles signed RHP Garrett Farmer. | |
| Baltimore Orioles signed LHP Dillon McCollough. | |
| Baltimore Orioles sent RHP Nate Karns on a rehab assignment to GCL Orioles. | |
| Baltimore Orioles sent OF DJ Stewart on a rehab assignment to GCL Orioles. | |
| Boston Red Sox signed free agent RHP Mason Duke to a minor league contract. | |
| New York Mets sent RHP Noah Syndergaard on a rehab assignment to Brooklyn Cyclones. | |
| New York Yankees activated DH Kendrys Morales from the 10-day injured list. | |
| New York Yankees designated DH Kendrys Morales for assignment. | |
| New York Yankees recalled LHP Stephen Tarpley from Scranton/Wilkes-Barre RailRiders. | |
| Boston Red Sox optioned RHP Josh A. Smith to Pawtucket Red Sox. | |
| Boston Red Sox activated RHP Steven Wright from the restricted list. | |
| Boston Red Sox transferred RHP Nathan Eovaldi from the 10-day injured list to the 60-day injured list. Loose body in the right elbow. | |
| St. Louis Cardinals optioned LHP Genesis Cabrera to Memphis Redbirds. | |
| St. Louis Cardinals recalled RHP Daniel Ponce de Leon from Memphis Redbirds. | |
| St. Louis Cardinals recalled RHP Dominic Leone from Memphis Redbirds. | |
| St. Louis Cardinals placed RHP Jordan Hicks on the 10-day injured list retroactive to June 23, 2019. Torn UCL in right elbow. | |
| Atlanta Braves optioned RHP Chad Sobotka to Gwinnett Stripers. | |
| Atlanta Braves activated LHP Sean Newcomb from the 7-day injured list. | |
| Baltimore Orioles claimed RHP Tayler Scott off waivers from Seattle Mariners. | |
| Baltimore Orioles designated LHP Sean Gilmartin for assignment. | |
| Baltimore Orioles optioned RHP Tayler Scott to Norfolk Tides. | |
| Miami Marlins activated 1B Neil Walker from the 10-day injured list. | |
| Texas Rangers activated CF Joey Gallo from the 10-day injured list. | |
| Oakland Athletics selected the contract of SS Taylor Motter from New Britain Bees. | |
| Tampa Bay Rays signed free agent OF Izzy Wilson to a minor league contract. | |
| Washington Nationals optioned RHP Kyle McGowin to Fresno Grizzlies. | |
| Washington Nationals selected the contract of RHP Fernando Rodney from Fresno Grizzlies. | |
| Washington Nationals selected the contract of LHP Jonny Venters from Harrisburg Senators. | |
| Los Angeles Angels sent SS Andrelton Simmons on a rehab assignment to Inland Empire 66ers. | |
| Philadelphia Phillies sent RHP Tommy Hunter on a rehab assignment to Reading Fightin Phils. | |
| Houston Astros sent RHP Joe Smith on a rehab assignment to Round Rock Express. | |
| Minnesota Twins designated LHP Gabriel Moya for assignment. | |
| Texas Rangers released LHP Drew Smyly. | |
| Texas Rangers sent OF Scott Heineman on a rehab assignment to Nashville Sounds. | |
| San Diego Padres sent RHP Kazuhisa Makita outright to Amarillo Sod Poodles. | |
| Washington Nationals transferred RHP Jeremy Hellickson from the 10-day injured list to the 60-day injured list. Stiff right shoulder. | |
| Colorado Rockies placed 2B Brendan Rodgers on the 10-day injured list. Right shoulder impingement. | |
| Colorado Rockies selected the contract of RHP Chi Chi Gonzalez from Albuquerque Isotopes. | |
| 06/24/19 | Houston Astros signed LHP Whit Drennan. |
| 1B Parker Phillips assigned to Minnesota Twins. | |
| CF Bryson Gandy assigned to Minnesota Twins. | |
| Texas Rangers optioned LHP Kyle Bird to Nashville Sounds. | |
| Chicago White Sox activated CF Jon Jay from the 60-day injured list. | |
| Chicago White Sox designated RHP Odrisamer Despaigne for assignment. | |
| Cleveland Indians recalled RHP Jon Edwards from Columbus Clippers. | |
| Cleveland Indians optioned RHP Aaron Civale to Columbus Clippers. | |
| Colorado Rockies sent LHP Harrison Musgrave on a rehab assignment to Albuquerque Isotopes. | |
| Cincinnati Reds sent 2B Scooter Gennett on a rehab assignment to Louisville Bats. | |
| Minnesota Twins signed free agent RHP Cody Allen to a minor league contract. | |
| Philadelphia Phillies optioned Enyel De Los Santos to Lehigh Valley IronPigs. | |
| Philadelphia Phillies transferred LF Andrew McCutchen from the 10-day injured list to the 60-day injured list. Left ACL tear. | |
| Philadelphia Phillies selected the contract of RHP Fernando Salas from Lehigh Valley IronPigs. | |
| Atlanta Braves recalled RHP Kyle Wright from Gwinnett Stripers. | |
| Miami Marlins sent LHP Caleb Smith on a rehab assignment to Jacksonville Jumbo Shrimp. | |
| Atlanta Braves optioned LHP Grant Dayton to Gwinnett Stripers. | |
| Baltimore Orioles signed C Adley Rutschman. | |
| Philadelphia Phillies sent CF Adam Haseley on a rehab assignment to Reading Fightin Phils. | |
| Houston Astros optioned LHP Reymin Guduan to Round Rock Express. | |
| Detroit Tigers sent RHP Carlos Torres outright to Toledo Mud Hens. | |
| RHP Erick Fedde assigned to Fresno Grizzlies from Washington Nationals. | |
| Houston Astros optioned RHP Rogelio Armenteros to Round Rock Express. | |
| Houston Astros activated RF George Springer from the 10-day injured list. | |
| Houston Astros activated RHP Collin McHugh from the 10-day injured list. | |
| Miami Marlins optioned RHP Jeff Brigham to New Orleans Baby Cakes. | |
| St. Louis Cardinals optioned LHP Genesis Cabrera to Memphis Redbirds. | |
| Detroit Tigers signed RHP Ted Stuka. | |
| Philadelphia Phillies signed free agent SS Kervin Pichardo to a minor league contract. | |
| Baltimore Orioles signed RHP Jensen Elliott. | |
| New York Yankees signed LHP Matt Minnick. | |
| New York Yankees signed LHP Michael Giacone. | |
| New York Yankees signed LHP Gerrit van Zijll. |