Best will initially spend a month with the Cherries

Best, 19, has joined the Cherries from south coast neighbours Southampton, initially on a month's loan with a view to extending his stay.

Meanwhile, 18-year-old Ainsworth has moved to Dean Court from Derby County in a deal lasting until 1 January 2007.

Ainsworth arrived at Bournemouth last week, and played in Saturday's 4-0 friendly defeat by Portsmouth.

Best made his Saints debut on his 18th birthday in September 2004, and has made eight first-team appearances for them in the last two seasons.

He has also served QPR on loan - and had two loan spells at Sheffield Wednesday last season.