subquery without mysql subquery?

[Anonymous]

1. find the last 20 rounds score (I am already done that in my SELECT statement).
2. from my result I want to sort the score field. - Need help here.
3. pick the 10 best scores (from the score field). - Need help here.
4. then do my formula below to get my handicap. - Need improvement is available.

pick up the scores in an array do a reverse array sort...