Garrett Gomez guided her from last - more than 17 lengths behind - to a 2 1/2-length victory in Friday's $2 million race at Santa Anita. Life Is Sweet was one of four longshots to win on the opening day of the 26th annual world championships.
"It was exhilarating," co-owner Marty Wygod said.
The 4-year-old filly shares the barn of defending champion Zenyatta, who stayed in her stall resting ahead of Saturday's $5 million Classic against the boys. She will put her 13-0 winning streak on the line in the 1 1/4-mile race, the richest in North America.
Both horses are trained by John Shirreffs for different owners.
"I was glad she was able to get it done today," Shirreffs said. "She really deserves this. She had been coming into this race really great."
Life Is Sweet ran 1 1-8 miles in 1:48.58 and paid $18.20, $8 and $5 at 8-1 odds.
Mushka returned $12.80 and $6.40, while Music Note was another length back in third for the second straight year and paid $3.20 to show. Careless Jewel, the 9-5 wagering favorite, romped to an early nine-length lead before fading to last in the field of eight. Cocoa Beach, second last year, was sixth.
"She locked onto the bridle and went as far as she could as fast as she could. That's not her," said Robert Landry, who rode Careless Jewel. "It's disappointing because she's a much better filly than she showed."
American horses won four of the day's six races, with jockey Julien Leparoux riding two winners on a day that went off without incident to horses or riders.
It was the second consecutive Breeders' Cup to be run on Santa Anita's synthetic Pro-Ride surface, which kept stellar filly Rachel Alexandra away. She was 8 for 8 this year, including three wins over male horses, one of them in the Preakness. But her owner Jess Jackson doesn't like synthetics, so he shut down the Horse of the Year favorite.
Life Is Sweet had lost to Zenyatta in three of her previous four races. She improved to 4 for 5 this year in races where Zenyatta wasn't running, with her only loss to males in the Hollywood Gold Cup.
"If you have to be overshadowed by something, that is the right mare to be overshadowed by," Wygod said. "She's a great, great mare."
Life Is Sweet went from last midway through the final turn to the front with a run on the far outside. She overcame getting pinched out of the starting gate.
"I'm glad she picked today to show up," Gomez said. "When you run some tough races like she did, it will take something out of you. I'm glad they were able to get her confidence back and have her prepared."
It was the sixth win in 15 career starts - and fourth on a synthetic track - for the filly, whose training was disrupted by severe muscle cramping in July and August.
"I knew Life Is Sweet was going to really put in a tremendous run. I told that to Garrett before he got up on her," Marty Wygod said. "When I saw those fractions, I realized we had a good shot. She did it easily. She really did."
Man of Iron opened the card with a thrilling nose victory over 9-year-old gelding Cloudy's Knight in the $500,000 Marathon, the day's only race featuring males.
Man of Iron covered 1 3/4 miles in 2:54.11 under John Murtagh, giving Irish trainer Aidan O'Brien his fourth career Breeders' Cup victory. The 3-year-old paid $14.80 to win in his U.S. debut after running exclusively in Europe.
Rosemary Homeister Jr. barely missed becoming the second woman to ride a Breeders' Cup winner, losing the photo finish by a bob of her gelding's head.
Midday gave Europe its other victory, winning the $2 million Filly & Mare Turf by a length and snapping an 0 for 6 streak in the Breeders' Cup by veteran European trainer Henry Cecil.
Ridden by Thomas Queally, Midday ran 1 1/4 miles in 1:59.14 and paid $6.60 to win.
She Be Wild charged along the rail to win the $2 million Juvenile Fillies by three-quarters of a length under Leparoux. She ran 1 1-16 miles in 1:43.80 and paid $16.80 to win, and improved to 4 for 5 on synthetic surfaces.
It was trainer Wayne Catalano's second career Breeders' Cup victory.
The $1 million Juvenile Fillies Turf was won by Tapitsfly, who held off Rose Catherine by a half-length. With Robby Albarado aboard, Tapitsfly ran one mile in 1:34.25 and paid $21.60 to win.
Informed Decision won the $1 million Filly & Mare Sprint by 1 1/4 lengths over defending champion Ventura, giving Leparoux his other win. The 4-year-old gray filly covered 7 furlongs in 1:21.66 and paid $8.80 to win.
Trainer Jonathan Sheppard scored his first Breeders' Cup victory on the day, to go with a second by Cloudy's Knight and a third by Forever Together in the Filly & Mare Turf.
Ventura went off the 4-5 wagering favorite. She is trained by Hall of Famer Bobby Frankel, who has run his stable by phone most of the year as he battles an undisclosed illness. His other horses, Proviso in the Ladies' Classic and Visit in the Filly & Mare Turf, both finished fourth.
