| Last updated: Tue, September 19, 2017, 14:46 EDT | ||
| Tuesday, September 19, 2017 | ||
| Team | Player | Transaction |
| Cincinnati Reds | D.J. Peterson | Called Up from Minors, - Not to Report |
| Monday, September 18, 2017 | ||
| Team | Player | Transaction |
| Chicago Cubs | Willson Contreras | Reinstated From League Suspension |
| Cincinnati Reds | Barrett Astin | Outrighted to Minors |
| San Diego Padres | Tim Melville | Called Up from Minors |
| San Diego Padres | Travis Jankowski | Called Up from Minors |
| San Diego Padres | Hunter Renfroe | Called Up from Minors |
| San Diego Padres | José Valdez | Designated for Assignment |
| San Diego Padres | Christian Villanueva | Purchased From Minors |
| San Diego Padres | Rocky Gale | Purchased From Minors |
| San Diego Padres | Dusty Coleman | Designated for Assignment |
| Sunday, September 17, 2017 | ||
| Team | Player | Transaction |
| Baltimore Orioles | Richard Rodríguez | Designated for Assignment |
| Baltimore Orioles | Tanner Scott | Purchased From Minors |
| Baltimore Orioles | Richard Rodríguez | Outrighted to Minors |
| Chicago Cubs | Willson Contreras | Starting to Serve Suspension |
| Cincinnati Reds | Drew Storen | Transferred to 60-Day DL, (Right elbow surgery - out for season) |
| Cleveland Indians | Jason Kipnis | Removed From 10-Day DL, (Recurring strained right hamstring) |
| Houston Astros | Colin Moran | Removed From 10-Day DL, (Facial fractures) |
| Houston Astros | Colin Moran | Recalled From Minors, Rehab Assignment |
| Kansas City Royals | Danny Duffy | Removed From 10-Day DL, (Left elbow impingement) |
| New York Yankees | Domingo Germán | Called Up from Minors |
| San Francisco Giants | Ryan Vogelsong | Signed to a Minor League Contract |
| San Francisco Giants | Ryan Vogelsong | Retired |
| Saturday, September 16, 2017 | ||
| Team | Player | Transaction |
| Chicago Cubs | Willson Contreras | Suspension Announced By League, (two games, reduced to one) |
| Chicago Cubs | Addison Russell | Removed From 10-Day DL, (Strained right foot) |
| Kansas City Royals | Joakim Soria | Removed From 10-Day DL, (Strained left oblique) |
| New York Yankees | Miguel Andújar | Called Up from Minors |
| New York Yankees | Jonathan Holder | Called Up from Minors |
| New York Yankees | Caleb Smith | Placed on 10-Day DL, (Viral infection) |
| Friday, September 15, 2017 | ||
| Team | Player | Transaction |
| Atlanta Braves | Jason Motte | Removed From 10-Day DL, (Right oblique strain) |
| Chicago White Sox | Willy Garcia | Recalled From Minors, Rehab Assignment |
| Chicago White Sox | Willy Garcia | Removed From 10-Day DL, (Concussion) |
| Detroit Tigers | Dixon Machado | Reinstated from Paternity Leave List |
| Los Angeles Angels | Brooks Pounders | Outrighted to Minors |
| Milwaukee Brewers | Yadiel Rivera | Designated for Assignment |
| Milwaukee Brewers | Aaron Wilkerson | Purchased From Minors |
| Seattle Mariners | James Paxton | Removed From 10-Day DL, (Strained left pectoral muscle) |
| Tampa Bay Rays | Jacob Faria | Removed From 10-Day DL, (Left abdominal strain) |
| Tampa Bay Rays | Jacob Faria | Recalled From Minors, Rehab Assignment |
| Texas Rangers | Tyson Ross | Cleared Waivers and Became a Free Agent |
| Thursday, September 14, 2017 | ||
| Team | Player | Transaction |
| Atlanta Braves | Tony Sánchez | Outrighted to Minors |
| Atlanta Braves | Danny Santana | Recalled From Minors, Rehab Assignment |
| Boston Red Sox | David Price | Removed From 10-Day DL, (Left elbow inflammation) |
| Cleveland Indians | Andrew Miller | Removed From 10-Day DL, (Right patellar tendinitis) |
| Houston Astros | Mike Fiers | Suspension Announced By League, (five games) |
| Houston Astros | Mike Fiers | Starting to Serve Suspension |
| Kansas City Royals | Onelki García | Outrighted to Minors |
| Los Angeles Dodgers | Fabio Castillo | Outrighted to Minors |
| Milwaukee Brewers | Jimmy Nelson | Placed on 10-Day DL, (Strained right rotator cuff) |
| Pittsburgh Pirates | Drew Hutchison | Outrighted to Minors |
| Pittsburgh Pirates | Drew Hutchison | Called Up from Minors, - Not to Report |
| San Francisco Giants | Engelb Vielma | NTR - Acquired Off Waivers from Twins, Minnesota |
| San Francisco Giants | Michael Morse | Transferred to 60-Day DL, (Concussion) |
| Seattle Mariners | Felix Hernandez | Removed From 10-Day DL, (Re-aggravated right shoulder bursitis) |
| Wednesday, September 13, 2017 | ||
| Team | Player | Transaction |
| Baltimore Orioles | Andrew Faulkner | Outrighted to Minors |
| Chicago Cubs | Jen-Ho Tseng | Purchased From Minors |
| Chicago Cubs | Pierce Johnson | Designated for Assignment |
| Cincinnati Reds | Drew Storen | Placed on 10-Day DL, (Right elbow surgery - out for season) |
| Detroit Tigers | Arcenio León | Cleared Waivers and Became a Free Agent |
| Minnesota Twins | Adalberto Mejía | Recalled From Minors, Rehab Assignment |
| Minnesota Twins | Héctor Santiago | Recalled From Minors, Rehab Assignment |
| Minnesota Twins | Adalberto Mejía | Removed From 10-Day DL, (Left arm brachialis strain) |
| Philadelphia Phillies | Daniel Nava | Placed on 60-Day DL, (Back strain) |
| Philadelphia Phillies | Henderson Alvarez | Purchased From Minors |
| St. Louis Cardinals | Jedd Gyorko | Removed From 10-Day DL, (Right hamstring strain) |
| Tuesday, September 12, 2017 | ||
| Team | Player | Transaction |
| Baltimore Orioles | Craig Gentry | Removed From 10-Day DL, (Fractured right finger) |
| Boston Red Sox | Kyle Martin | Outrighted to Minors |
| Cincinnati Reds | Keury Mella | Called Up from Minors |
| Cincinnati Reds | Barrett Astin | Designated for Assignment |
| Cincinnati Reds | Deck McGuire | Purchased From Minors |
| Cincinnati Reds | Jesse Winker | Removed From 10-Day DL, (Left hip flexor strain) |
| Detroit Tigers | Dixon Machado | Placed on Paternity Leave List |
| Kansas City Royals | Onelki García | Designated for Assignment |
| Kansas City Royals | Mike Morin | Acquired Off Waivers From from Angels, Los Angeles |
| Los Angeles Angels | Vicente Campos | Cleared Waivers and Became a Free Agent |
| Minnesota Twins | Gabriel Moya | Purchased From Minors |
| Minnesota Twins | Engelb Vielma | Designated for Assignment |
| New York Mets | Tomas Nido | Called Up from Minors |
| Philadelphia Phillies | Andrew Knapp | Removed From 10-Day DL, (Right hand contusion) |
| Philadelphia Phillies | Zach Eflin | Transferred to 60-Day DL, (Right shoulder strain) |
| Philadelphia Phillies | Víctor Arano | Purchased From Minors |
| San Diego Padres | Cory Mazzoni | Purchased From Minors |
| San Diego Padres | Carter Capps | Placed on 60-Day DL, (Blood clots) |
| St. Louis Cardinals | Magneuris Sierra | Called Up from Minors |
| Texas Rangers | Willie Calhoun | Purchased From Minors |
| Texas Rangers | Tyson Ross | Released |
| Texas Rangers | Keone Kela | Removed From 10-Day DL, (Right shoulder soreness) |
| Texas Rangers | Adrian Beltre | Removed From 10-Day DL, (Strained left hamstring) |
| Toronto Blue Jays | Russell Martin | Removed From 10-Day DL, (Strained left oblique) |
| Monday, September 11, 2017 | ||
| Team | Player | Transaction |
| Cleveland Indians | Daniel Robertson | Released |
| Detroit Tigers | Arcenio León | Released |
| Detroit Tigers | Tyler Collins | Purchased From Minors |
| New York Yankees | Clint Frazier | Removed From 10-Day DL, (Left oblique strain) |
| New York Yankees | Clint Frazier | Recalled From Minors, Rehab Assignment |
| Philadelphia Phillies | Zac Curtis | Acquired Off Waivers From from Mariners, Seattle |
| Philadelphia Phillies | Jesen Therrien | Placed on 60-Day DL, (Right elbow strain) |
| Seattle Mariners | Ryan Weber | Outrighted to Minors |
| Seattle Mariners | Ryan Weber | Recalled From Minors, Rehab Assignment |
| Seattle Mariners | Ryan Weber | Removed From 60-Day DL, (Right biceps strain) |
| St. Louis Cardinals | Breyvic Valera | Sent to Minors |
| Sunday, September 10, 2017 | ||
| Team | Player | Transaction |
| Arizona Diamondbacks | Randall Delgado | Recalled From Minors, Rehab Assignment |
| Arizona Diamondbacks | Christian Walker | Purchased From Minors |
| Arizona Diamondbacks | Randall Delgado | Transferred to 60-Day DL, (Right elbow inflammation) |
| Chicago Cubs | Willson Contreras | Recalled From Minors, Rehab Assignment |
| Chicago Cubs | Willson Contreras | Removed From 10-Day DL, (Strained right hamstring) |
| Colorado Rockies | Tyler Anderson | Removed From 60-Day DL, (Left knee inflammation) |
| Colorado Rockies | Tyler Anderson | Recalled From Minors, Rehab Assignment |
| Colorado Rockies | Jairo Díaz | Placed on 60-Day DL, (Right elbow inflammation) |
| Colorado Rockies | Jairo Díaz | Called Up from Minors |
| Los Angeles Angels | Vicente Campos | Released |
| Pittsburgh Pirates | Dan Runzler | Purchased From Minors |
| Pittsburgh Pirates | Edgar Santana | Called Up from Minors |
| Pittsburgh Pirates | Jacob Stallings | Called Up from Minors |
| Pittsburgh Pirates | Tyler Glasnow | Called Up from Minors |
| Pittsburgh Pirates | Johnny Barbato | Called Up from Minors |
| Pittsburgh Pirates | Josh Harrison | Transferred to 60-Day DL, (Fractured metacarpal, left hand) |
| Pittsburgh Pirates | Jack Leathersich | Called Up from Minors |
| Tampa Bay Rays | Jake Faria | Sent to Minors, For Rehabilitation |
| Texas Rangers | Matt Bush | Removed From 10-Day DL, (MCL sprain, right knee) |
