The 20-cent Rainbow pick six will have a mandatory payout on Sunday at Santa Anita, the track announced on Monday.

Officials expect the pool to reach $3 million. 

The Rainbow carryover portion of the bet was $261,756 for Monday's program. The Rainbow carryover portion is paid out only when there is one winning ticket or a day with a mandatory payout.

Aside from Monday, there is racing on Friday and Saturday before Sunday's mandatory payout. There is a chance the carryover could surpass $500,000 by then, or that one ticket holder will have scooped a lucrative pool.