Most Group 1/Grade 1 flat races won by a trainer in a calendar year
- Who
- Aidan O'Brien
- What
- 28 total number
- Where
- Not Applicable
- When
- 10 December 2017
The most Group 1/Grade 1 flat races won by a trainer in a calendar year is 28, by Aidan O’Brien (Ireland) in 2017. He surpassed the record of 25 – set by Bobby Frankel in 2003 – when his horse Saxon Warrior won the Racing Post Trophy in Doncaster, South Yorkshire, UK, on 28 October 2017. O’Brien’s most prolific horse was Winter, which won four Group 1 races, while both Roly Poly and Highland Reel won three each. He triumphed in an unprecedented eight out of the 10 British and Irish Classics in 2017.
Group 1/Grade 1 races are considered to be the highest level of flat races in many countries.