Win No. 9,531 came in the fourth race, when the 48-year-old Baze found a hole along the rail and drove through it to win on the Longden turf course, named for Johnny Longden, who once held the record Baze broke.
Baze doffed his riding helmet to the cheering crowd.
Pincay had owned the mark since Dec. 10, 1999, when he took it from Bill Shoemaker. Pincay, 59, was on hand for his fifth day of watching Baze, who had won once in each of the previous two days. Baze tied the record of 9,530 on Thursday.
Shoemaker had held the mark for 29 years after surpassing Longden.
"Who would've thought 32 years ago a skinny little kid with no experience would be standing here today," Baze told the sparse crowd as he stood in the winner's circle. "I could hardly believe this would happen."
The record is the crowning achievement of a career that began with Baze's first winner in 1974 at Yakima Meadows, Washington, riding a horse trained by his father.
Baze has spent the majority of his career in the San Francisco Bay Area, having tried the ultra-competitive Southern California circuit for three years in the late 1980s with little success.He has ridden in just two Kentucky Derbys 10 years apart, and is 0-for-3 in the Breeders' Cup World Thoroughbred Championship races.
Baze is not the legendary rider that Shoemaker, Pincay and Longden were, but he's respected for his dedication and competitive desire.
"Russell is a great rider and he works very hard," Pincay told the fans. "It takes a lot of ability and dedication to win that many races."
Baze is the dominant rider in the Bay Area, leaving other jockeys scrambling to get mounts that routinely fall to him simply because of reputation. He has won 36 riding titles at Bay Meadows, the track where Seabiscuit ran.
The track presented Baze and his wife, Tami, with a European vacation.
Baze's only son, Gable, missed three days' of school waiting for his father to make history.
Leading Riders by Wins (Through Dec. 1)
1. x-Russell Baze, 9,531
2. Laffit Pincay, Jr., 9,530
3. William Shoemaker, 8,833
4. Pat Day, 8,803
5. David Gall, 7,396
6. Chris McCarron, 7,141
7. Angel Cordero, Jr., 7,057
8. Jorge Velasquez, 6,795
9. Sandy Hawley, 6,449
x-Earlie Fires, 6,403
x--Indicates active riderRussell Baze Facts
By The Associated Press
NAME: Russell Avery Baze
AGE: 48 (Born Aug. 7, 1958)
BIRTHPLACE: Vancouver, British Columbia
WEIGHT: 115 pounds
FAMILY: Wife Tami; daughters Trinity, Brandi and Cassie; son Gable
1974 - Rode first winner, Oregon Warrior, at Yakima Meadows, Wash., trained
by father, Joe
1980 - First full season riding in Bay Area after arriving from Washington
March 1988 - Began riding full-time on Southern California circuit
Dec. 1988 - Rode 3,000th winner, Hagley's Lion, at Hollywood Park,
July 1991 - Left Southern California circuit to return full-time to Bay Area
1992 - Rode seven winners in one day at Golden Gate Fields, Albany, Calif.
1993 - Rode 4,000th winner, Frank Musso, at Golden Gate Fields
1995 - Rode 5,000th winner, Cyrus Says, Sonoma County Fair, Santa Rosa,
1996 - Rode in first Kentucky Derby, finished 14th aboard Semoran
1997 - Rode 6,000th winner, Clover Hunter, at Golden Gate Fields
2000 - Rode 7,000th winner, This is the Moment, Alameda County Fair,
2002 - Rode 8,000th winner, Ourwhistlebritches, at Bay Meadows, San Mateo,
1998 - Led nation in victories for seventh consecutive year with 404
1999 - Inducted into thoroughbred racing's Hall of Fame
Jan. 2005 - Passed Bill Shoemaker for second place on career victory list,
riding his 8,834th winner, Hollow Memories, at Golden Gate Fields
June 2005 - Rode 9,000th winner, Queen of the Hunt, at Golden Gate Fields
Dec. 1, 2006 - Passed Laffit Pincay Jr. for first place on career victory
list, riding his 9,531st winner, Butterfly Belle, at Bay Meadows.