McKinzie, Bolt D’Oro square off in San Felipe Stakes at Santa Anita

The two best 3-year-old horses in the country are supposed to meet for the first time in the Kentucky Derby, not in early March.

Two years ago, the best the West had to offer, Nyquist, met the best from the East, Mohaymen, in the Florida Derby. Nyquist won that race and then the Kentucky Derby. Mohaymen never won another race.

So, it’s no surprise that Saturday’s $400,000 San Felipe Stakes at Santa Anita has generated national interest for a race that is not even the final prep for the Derby.

Bob Baffert, trainer of undefeated and slight favorite McKinzie, and Mick Ruis, trainer of Bolt D’Oro, are somewhere between optimistic and realistic.

“This is when it all starts,” Baffert said. “This race is the last chance for you to make a little bit of a mistake.”

Ruis also tempered expectations.

“Would I be totally disappointed if we didn’t win?” Ruis said. “No, because it’s a steppingstone. But I’m not making excuses for him if he loses. I think he can win.”

There is another factor that neither trainer can control: the weather. Rain is supposed to start late in the morning and continue unabated for the remainder of the day. Both trainers say they plan to run their horses regardless of the quality of the surface.

“Actually, when it gets more moisture in it, it’s a better track,” Baffert said. “I don’t like it when it’s real dry. When it’s wet, they do better.”

Earlier in the week, Ruis said he would scratch Bolt D’Oro if it was a wet surface. On Friday, he backed off that.

“We’re running [Saturday],” Ruis said. “I like to give ammunition to all those people who like to second-guess me.”

In addition to the Kentucky Derby-points bearing San Felipe, there are three Grade 1 races including the Santa Anita Handicap, once the biggest race of the meeting. Now, because of the addition of the multi-million dollar races at Gulfstream in late January and Dubai later this month, the fields are not as strong.

The purse is $600,000, down from $1 million a few years ago.

All of which is why the San Felipe is now the day’s main attraction.

McKinzie and Bolt D’Oro come into the race from different paths.

McKinzie, named for late Los Alamitos executive Brad McKinzie, a close friend of Baffert, has been brought along in an orderly path, winning his debut on Oct. 28, being placed first in the Grade 1 Los Alamitos Futurity after stablemate Solomini was disqualified, and posting an easy 3 ½-length win in the Sham Stakes.

Bolt D’Oro was the hottest 2-year-old in the country, winning two Grade 1s, including a 7 ¾-length romp in the FrontRunner Stakes. He went off as the favorite in the Breeders’ Cup Juvenile but finished third, running wide the entire trip.

Earlier this year, Bolt D’Oro pulled a muscle, canceling a projected start in the San Vicente Stakes.

Ruis waited a couple months after the Breeders’ Cup before replacing jockey Corey Nakatani with East Coast-based Javier Castellano, a three-time Eclipse Award winner.

“I wasn’t really happy with the Breeders’ Cup, but I didn’t want to have sour grapes and say how I was disappointed [with the ride],” Ruis said. “I let everybody else say what kind of ride that was. I’ve known Corey for a long time and he’s a great rider. But we wanted to train the horse and do it our way and to make a good plan.”

That plan did not include Nakatani. But Castellano, one of the most in-demand jockeys in the country, has not committed to ride Bolt D’Oro beyond the San Felipe.

“It’s up to Javier after this race,” Ruis said. “After the San Felipe, he’s going to have to make his decision. I’m not waiting two weeks for him to ride another horse. If he wants to ride him, we’ll welcome him, but I’m not going to wait until the last minute when I have Victor [Espinoza] waiting in the shadows.”

Espinoza, a Hall of Famer who has won three Kentucky Derbies and the Triple Crown, has worked Bolt D’Oro and is ready to commit to him for the Derby.

Saturday’s race is only 1 1/16 miles and has eight expected starters, including Lombo, winner of the Robert Lewis Stakes, and Kanthaka, who has won his last two races, including the San Vicente.

“There are some good horses in there, but a mile and an eighth is when they start to separate themselves,” Baffert said. “At 1 1/16, they are all going to be kind of close. I think Bolt and McKinzie are the two standouts in the race, but they still have to get good racing luck.”

Expect some separation Saturday.

sports@latimes.com