Deputies with the sheriff's San Xavier District responded to the home after receiving a report of an assault.
Authorities said the intruder entered through an unlocked door, physically and sexually assaulted the victim, then tried to burglarize the home before fleeing. No arrests had been announced as of Tuesday.
The suspect is described as either Hispanic or White, about 5 feet 10 inches tall with a thin build. He has gray in his beard and was last seen wearing an oversized green shirt.
The home invasion occurred about 30 miles from the Catalina Foothills home where 84-year-old Guthrie, the mother of "Today" co-anchor Savannah Guthrie, disappeared on Feb. 1 in a case that remains under investigation by the FBI and the sheriff's department.
Fox News Digital reported Tuesday that FBI Director Kash Patel said a four-day delay before the FBI joined the Guthrie investigation may have cost investigators crucial video evidence.
Patel accused the sheriff's department of keeping the bureau "out of the investigation" for four days after Guthrie's disappearance.
Nanos has disputed Patel's account, saying the FBI was notified promptly and worked alongside investigators.
Authorities in the Guthrie case have said the unidentified person seen outside her home was believed to be between 5 feet 9 inches and 5 feet 10 inches tall.
The sheriff's department is urging residents who live near the crime scene to review home security or neighborhood surveillance footage that may help identify the suspect.
Anyone with information about the home invasion is asked to call 911 or submit an anonymous tip to 88-CRIME.
The FBI did not immediately respond to Fox News Digital's request for comment on the investigation.