Police acted after the former Southampton star told them he had genuine fears for his safety.
The mum, 37, who had allegedly pestered the £6m star at his old club, turned up three weeks ago at his new club Everton.
She had got into the pre-season training ground and allegedly tried to follow him home.
An Everton club source said: "The moment he saw her he realised he had a major problem."
Police were called and the source claimed the woman, of Southampton, told them Beattie was her boyfriend. "She was completely deluded he was in love with her."
She is believed to be detained for 28 days in a secure hospital in Winchester, Hamps.
Last night, an Everton spokesman said: "There was an incident. The matter has been resolved to our satisfaction."
the above was in the daily mirror but it also begs the question "why has Beattie not been locked up for pretending to be a striker all these years"? it seems they are both deluded
