Gun Runner Is the New Into Mischief
Five years of Keeneland September Book 1 data show a changing of the guard at the top of the yearling market.
For years, Into Mischief has occupied a pretty enviable position at the Keeneland September Yearling Sale.
He is the sire everyone wants to have in the catalog. Buyers know what they are getting. Sellers know there will be an audience. Put the right Into Mischief yearling in Book 1 and there will be plenty of people standing around the back ring when the horse comes out.
Our five-year look at Keeneland September Book 1 suggests another stallion has joined him at the very top of the market.
And in 2026, he passed him.
Gun Runner is the new Into Mischief.
At least in Book 1.
That qualification matters. This is a study of the yearling market, not an argument about which stallion is better. We analyzed every Book 1 result from 2022 through 2026, covering 1,853 cataloged yearlings and 1,120 sales. What emerges is a remarkable shift in how buyers have valued the two stallions at the most selective end of Keeneland September.
Five Years Ago
In 2022, Into Mischief was already Into Mischief.
His Book 1 yearlings grossed $19.3 million.
Gun Runner's gross was $8.6 million.
Gun Runner averaged $536,562 and produced two seven-figure Book 1 yearlings. He was already a major sire with a major market.
Into Mischief was operating on another level.
A year later, the gap became enormous. Into Mischief's 2023 Book 1 gross reached $28.3 million, while Gun Runner's fell to $6.6 million. That $28.3 million remains the high-water mark for any sire in our five-year Book 1 dataset.
By 2024, Gun Runner's Book 1 gross had jumped to $18.8 million. It climbed to $24.6 million in 2025 and $27.6 million this year.
Into Mischief moved the other way. After peaking at $28.3 million in 2023, his Book 1 gross fell to $16.0 million in 2024, $14.9 million in 2025 and $15.2 million in 2026.
| Year | Gun Runner | Into Mischief |
|---|---|---|
| 2022 | $8.6M | $19.3M |
| 2023 | $6.6M | $28.3M |
| 2024 | $18.8M | $16.0M |
| 2025 | $24.6M | $14.9M |
| 2026 | $27.6M | $15.2M |
Gross alone can fool you. The number of yearlings cataloged changes, horses scratch, and one extraordinary sale can move a sire's total by millions.
The rest of Gun Runner's 2026 numbers are even more interesting.
Figure 1 · The crossover
The lines cross in 2024 and never cross back
Show the data
| Year | Gun Runner Book 1 gross | Into Mischief Book 1 gross |
|---|---|---|
| 2022 | $8.6M | $19.3M |
| 2023 | $6.6M | $28.3M |
| 2024 | $18.8M | $16.0M |
| 2025 | $24.6M | $14.9M |
| 2026 | $27.6M | $15.2M |
Twelve Million-Dollar Yearlings
Gun Runner had 47 yearlings cataloged in Book 1 this year, the largest representation of any sire.
Twenty-five sold.
They averaged $1,104,000, with a $900,000 median.
And 12 brought at least $1 million.
Nearly half of the Gun Runners that sold in Book 1 were seven-figure yearlings.
Those 12 million-dollar horses also exceed Into Mischief's best year in our five-year dataset. Into Mischief produced 11 in 2023.
Three of the five highest-priced yearlings in Book 1 this year were by Gun Runner: a $3.1 million colt purchased by AMO Racing, a $2.8 million colt purchased by RTM Racing and a $2.3 million colt purchased by Coolmore.
Into Mischief Is Still Into Mischief
His market has hardly disappeared.
Into Mischief's 2026 Book 1 yearlings averaged $1,083,929, almost identical to Gun Runner's $1,104,000.
And the highest-priced horse among the two sires was the $3.7 million Into Mischief colt out of Grazie Mille, purchased by Coolmore's M.V. Magnier.
We know that page particularly well. Before Book 1, our racing-pedigree analysis ranked him fourth among all Book 1 colts based on Grazie Mille's production, juvenile-to-three-year-old development and an unusually interesting Into Mischief/Bernardini mating profile.
The difference shows up farther down the draft.
Into Mischief had 22 Book 1 yearlings reach the ring in 2026. Fourteen sold and eight went RNA, a 36 percent RNA rate.
Gun Runner had 33 reach the ring. Twenty-five sold and eight went RNA, a 24 percent RNA rate.
The best Into Mischiefs still command extraordinary prices. Buyers were simply more selective with the rest of his Book 1 group this year.
Gun Runner, meanwhile, supported a larger Book 1 population, a slightly higher average, stronger clearance and 12 seven-figure sales.
The Catalog Has Changed Too
Gun Runner had 27 Book 1 yearlings in 2022.
This year he had 47.
Into Mischief went from 51 Book 1 yearlings to 29 over the same period.
Book 1 placement reflects a series of judgments made long before the hammer falls, beginning with mating and breeding decisions and continuing through consignor strategy and sale placement.
Over five years, Gun Runner's Book 1 representation has grown from 27 hips to 47 while Into Mischief's has fallen from 51 to 29. The shift in catalog representation has occurred alongside an equally dramatic shift in buyer spending.
And Then There Is Not This Time
Not This Time had three yearlings cataloged in Book 1 in 2022. One sold, for $850,000.
This year he had 34 cataloged and 26 sold for $21.2 million, with an average of $815,769 and a 13 percent RNA rate.
His Book 1 gross has increased every year in between: $4.2 million, $10.5 million, $17.7 million and now $21.2 million.
Gun Runner has caught Into Mischief.
Not This Time is coming fast behind them.
More Money, Fewer Stallions
The larger Book 1 market helps explain the shift.
The average Book 1 yearling has risen 46 percent since 2022, from $499,128 to $727,885. The median has climbed from $450,000 to $600,000, and the number of seven-figure yearlings has grown from 22 to 41.
That money is also becoming more concentrated by sire.
The top five sires accounted for 50 percent of Book 1 gross in 2022. This year they accounted for 60 percent.
The top ten went from 75 percent to 85.5 percent.
Buyers are spending more at the top of the market and concentrating more of those dollars around a smaller group of stallions.
Right now, Gun Runner sits at the center of that group.
So, Is Gun Runner Really the New Into Mischief?
In Book 1, the market is treating him that way.
Five years ago, Into Mischief occupied a commercial position Gun Runner had yet to approach. This year their averages were almost identical, while Gun Runner led the book in gross, representation and seven-figure yearlings.
Into Mischief remains Into Mischief. His yearlings averaged more than $1 million, and his $3.7 million colt out of Grazie Mille was one of the stars of the sale.
This feels less like a king being deposed than another stallion reaching the same table.
And five years of Book 1 data suggest Gun Runner has arrived.
Thoroughbred Intelligence analyzed hip-level results from Keeneland September Book 1 for 2022 through 2026. Book 1 is defined as Sessions 1 and 2 in each year. The dataset covers 1,853 cataloged hips and 1,120 sales. The 2026 figures are through the close of Session 2 on September 16 and include 13 transactions marked pending settlement. RNA rates are calculated as RNAs divided by horses offered, excluding withdrawals.