Conversation so far:
Who were the California Angels?
The Los Angeles Angels are an American professional baseball team based in Anaheim, California.
Did Reginald Martinez Jackson join the California Angels?
The owner of the California Angels, entertainer Gene Autry, had heard of Jackson's desire to return to California to play, and signed him to a five-year contract.
Did the 1982 California Angels play well?
That 1982 season, the Angels won the American League West.

Question: How did he end up joining the Oakland athletics?
Self-contained rewrite: How did Reginald Martinez Jackson end up joining the Oakland Athletics?