Apprentice jockey J.C. Diaz, Jr. won four races on the first two days of the Los Alamitos summer meeting last weekend to take an early lead in the jockey standings. 

Diaz, 18, has four mounts on Thursday's nine-race program. If he rides a winner, it is likely to pay a price.

Diaz's first mount is Petronilla (7) who is 20-1 on the morning-line to win a maiden claimer in the fourth. In the fifth, he rides Hot Socks (3), who is 5-1 to win a maiden race for 2-year-old Cal-breds.

Diaz rides the final two races on Full Eclipse (1), who is 15-1 on the morning line in the eighth race, and R B Eye (8) in the ninth race, a maiden claimer. R B Eye is 4-1 on the morning line.