| Date | Transaction |
| 02-28-2083 | Don O'Brien has retired from the Orlando Mice. |
| 01-13-2081 | The Orlando Mice have moved Alex Barle to the active roster. The Orlando Mice have moved Don O'Brien to the inactive roster. |
| 11-13-2078 | Don O'Brien of the Orlando Mice is injured with an ankle ligament sprain and is expected to be out for approximately 30 days. |
| 11-21-2077 | Don O'Brien of the Orlando Mice is injured with a complete PCL tear and is expected to be out for the rest of the season. |
| 08-22-2077 | The Orlando Mice have moved Don O'Brien to the active roster. The Orlando Mice have moved Gary Watts to the inactive roster. |
| 08-09-2077 | The Orlando Mice have moved Hal Layne, Gary Watts, Craig DeGrenier, Brian Boykin, and Dick Tuinei to the active roster. The Orlando Mice have moved Billy Raffel, Don O'Brien, Sammie Nugent, Simon Fielder, and Chuck Lyons to the inactive roster. |
| 05-02-2077 | The Orlando Mice have moved Don O'Brien and Chuck Lyons to the active roster. The Orlando Mice have moved Hal Layne and Gary Watts to the inactive roster. |
| 02-07-2077 | The Orlando Mice have moved Ligarius Hall, Chuck Leblanc, Gary Watts, and Hal Layne to the active roster. The Orlando Mice have moved Chuck Lyons, Don O'Brien, John Hunt, Tom Caranci, and Dave Tanner to the inactive roster. |
| 11-30-2076 | The Orlando Mice have moved Fred Winder, Don O'Brien, John Hunt, Jack Kearns, Jeff Blackwell, and Joe Moriarty to the active roster. The Orlando Mice have moved Ligarius Hall, Chuck Leblanc, Frank Caranci, Dick Farrington, Gary Watts, and Hal Layne to the inactive roster. |
| 11-29-2076 | The Orlando Mice have moved Ligarius Hall, Chuck Leblanc, John Orton, Frank Caranci, Dick Farrington, Gary Watts, Hal Layne, and Billy Raffel to the active roster. The Orlando Mice have moved Tom Crawford, Fred Winder, Don O'Brien, John Hunt, Jack Kearns, Jeff Blackwell, Joe Moriarty, and Jerrol Schwartz to the inactive roster. |
| 09-06-2076 | The Orlando Mice have removed Don O'Brien from the trade block. |
| 12-30-2075 | The Orlando Mice have placed Don O'Brien on the trade block. |
| 10-28-2075 | The Orlando Mice have removed Don O'Brien from the trade block. |
| 09-30-2075 | The Orlando Mice have placed Don O'Brien on the trade block. |
| 12-16-2074 | The Orlando Mice have placed Don O'Brien on the Injured Reserve list for the remainder of the season. |
| 12-16-2074 | Don O'Brien of the Orlando Mice is injured with a leg contusion and is expected to be out for approximately 6 days. |
| 09-02-2074 | The Orlando Mice have moved Chris Whitley, Don O'Brien, Tom Crawford, and John Washington to the active roster. The Orlando Mice have moved Frank Carruth, Steve Romero, Daren Schroy, and Dave Woods to the inactive roster. |
| 08-27-2074 | The Orlando Mice have moved Frank Carruth, Steve Romero, Jim Beaudoin, and Dave Woods to the active roster. The Orlando Mice have moved Chris Whitley, Don O'Brien, Tom Crawford, and John Washington to the inactive roster. |
| 08-20-2074 | The Orlando Mice have removed Don O'Brien from the trade block. |
| 08-13-2074 | The Orlando Mice have moved Don O'Brien, Sammie Nugent, Tony Books, Chuck Lyons, and John Hunt to the active roster. The Orlando Mice have moved Hub Tuttle, Ed Hoaglin, Travis Hobert, Jim Beaudoin, and Willie Marston to the inactive roster. |
| 08-06-2074 | The Orlando Mice have moved Charley Tallant, Chuck Lyons, Willie Marston, and Dave Woods to the active roster. The Orlando Mice have moved Don O'Brien, John Hunt, Sammie Nugent, and Simon Fielder to the inactive roster. |
| 02-04-2074 | The Orlando Mice have placed Don O'Brien on the trade block. |
| 02-04-2074 | The Orlando Mice have placed Don O'Brien on the trade block. |
| 10-22-2073 | The Orlando Mice have moved Don O'Brien to the active roster. The Orlando Mice have moved Scott Robinson to the inactive roster. |
| 10-09-2073 | The Orlando Mice have moved Greg Fenimore and Johnny Robinson to the active roster. The Orlando Mice have moved Don O'Brien and Camp Beil to the inactive roster. |
| 10-08-2073 | Don O'Brien of the Orlando Mice is injured with a shoulder muscle strain and is expected to be out for approximately 14 days. |
| 09-03-2073 | The Orlando Mice have moved Tom Crawford, Bill Cain, Derrick Evans, Kendrick Easley, Don O'Brien, Tony Books, Fred Jackson, Tom Johnson, Roy Jester, Burt Ellison, Bill Spriggs, and Troy Holt to the active roster. The Orlando Mice have moved Rod Jurich, Sean Eckberg, Brenden Ross, Izzy Chapura, Dave Tanner, Tony Hix, Frank Carruth, and Stan Karamatic to the inactive roster. |
| 08-20-2073 | The Orlando Mice have moved Ron Williams, Milt Nettles, Izzy Chapura, Greg Fenimore, and Frank Carruth to the active roster. The Orlando Mice have moved Tom Crawford, Derrick Evans, Don O'Brien, Fred Jackson, and Tom Johnson to the inactive roster. |
| 04-30-2073 | Trade #87788 has been completed between the Orlando Mice and the Las Vegas Thunderbirds. The Las Vegas Thunderbirds receive Draft Pick - 2074 Round 2 (ORL) from the Orlando Mice in exchange for Don O'Brien (C). |
| 01-01-2073 | Don O'Brien of the Las Vegas Thunderbirds is injured with a mild concussion and is expected to be out for approximately 9 days. |
| 05-01-2072 | The Las Vegas Thunderbirds have placed Don O'Brien on the trade block. |
| 08-06-2068 | The Las Vegas Thunderbirds have moved George Davis, Tom Crawford, Don O'Brien, and Sammie Nugent to the active roster. The Las Vegas Thunderbirds have moved Dick Colhouer, Ray Loyd, and Robert Hobbs to the inactive roster. |
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