Fillies in the Belmont Stakes: Nest has a shot at accomplishing a rare feat

Of the three legs of the Triple Crown, none are as taxing as the Belmont Stakes. At 1 1/2 miles, it's the longest of the trio of races. There's a reason it's called the Test of the Champion.

The challenge is even harder for fillies. They have had some success in the Kentucky Derby (four wins) and the Preakness Stakes (six wins), but they have tended to not perform as well at Belmont Park.

MORE: Fast facts to know before picking a Belmont winner

This year, though, a filly may put together in a strong showing. The Todd Pletcher-trained Nest enters Saturday's race as a 7-1 choice.

Pletcher trained the last filly to win the Belmont — Rags to Riches in 2007. He says that it's not inconceivable that Nest can be the next one.

"It's something you see occasionally,” Pletcher told amNewYork's Christian Arnold. "It's not something you see often, but it's always exciting when you do. It's an extra challenge. In Nest’s case, she’s a filly that has a lot of pedigree and a lot of stamina in her pedigree for a race like this. That's a huge part of it."

We'll have to wait to find out if Nest can do it. In the meantime, The Sporting News has you covered on the history of fillies in the Belmont Stakes.

What is a filly?

A filly is a horse racing term for a young female horse. Globally, fillies tend to be female horses under 4 years old. In the United States and United Kingdom, the cutoff age for a horse to be considered a filly is 5.

When a filly reaches the age of 4 (or 5 in the U.S. and U.K.), they become a mare. Mare is the term used to describe an adult female horse.

The male equivalent for a filly is a colt. When a colt surpasses the age of 4/5, they are then called a stallion (if they are left uncastrated) or a gelding (if they are castrated).

How many fillies have won the Belmont Stakes?

Three fillies have won the Belmont Stakes in the race's 154-year existence.

It's rare for a filly to participate in the race at all — only 23 have taken part in the Belmont since its inception in 1867. In that debut race, filly Ruthless secured the victory, although the times were far slower than they are now.

The last time a filly won the Belmont Stakes was in 2007. Rags to Riches, carrying 121 pounds, overcame an early stumble to outlast Curlin by a head. The Todd Pletcher-trained horse was the first filly to claim victory in the competition in over a century.

The race has been run at various distances over the years. From 1867-1873, the race was run at 1 5/8 miles. In 1906, the race was 1 3/8 miles long.

Since 1925 (excluding 2020, when it was 1 1/8 miles), the Belmont has been a 1 1/2-mile race. Rags to Riches is the only filly to win the 1 1/2-mile version of the race.

Nest's Belmont Stakes odds

Nest is listed at 7-1 in updated odds by Sports Interaction. We the People and Mo Donegal are the co-favorites at 5-2.

MORE: Who will win the Belmont Stakes? 

Below are the betting odds for every horse in Saturday's Belmont Stakes, as of Friday evening: