Antongeorgi scored his victories for three different trainers, taking the fifth race with the Jerry Hollendorfer-trained Warren's Pepe ($7.00), the sixth race with the Lloyd Mason-conditioned Formally Yours ($17.20) and the eighth race with the Greg Gilchrist-trained Snuffy Smith ($6.60).
Hollendorfer and Mason both had training doubles. In addition to winning the fifth race, Hollendorfer took the seventh with Like A Tiger ($5.20). Mason captured the fourth race with Longitude ($3.40) and then completed his double when Formally Yours won the sixth.
The biggest upset on day No. 1 of the 67-day season was posted by the 3-year-old gelding First Takin, who, at odds of 45-to-1, won the third race by a nose over 2-to-1 favorite Kiss My Crown. Ridden by Saul Arias and trained by Gil Matos, First Takin paid $92.80.
Jockey Frank Alvarado scored the 1,999th win of his career when he won the first race of the meeting aboard Panchos Trickstar ($5.00). Alvarado has a good chance to get milestone win No. 2,000 Thursday as he has mounts in six races.
Post time for Thursday's eight-race program is 12:45 p.m.