MacGill, 50, was allegedly assaulted and then released.
Four men have been arrested.
About 8pm on April 14, MacGill was allegedly confronted by a 46-year-old man near Cremorne.
A short time later the pair was approached by two other men and MacGill was allegedly forced into a vehicle.
He was then driven to a property at Bringelly, in Sydney’s west, where the two men, plus another unknown man, allegedly assaulted MacGill and threatened him with a firearm.
About an hour later, MacGill was driven to nearby Belmore and released.
The incident was reported to officers from North Shore Police Area Command on April 20.
Officers are raiding homes at Sutherland, Caringbah, Brighton Le-Sands, Banksia and Marrickville.
MacGill was a leg-spin bowler who claimed 208 wickets in his 44 Test career.
Investigations are continuing.