Agnes Tachyon

2000: 2-year-old season

He made his debut relatively late, in a maiden race over 2,000 meters on the turf at Hanshin Racecourse in December 2000. Although he attracted much attention, being the full brother of Agnes Flight, his training times were not particularly impressive, so he was only the third favorite.^[4] However, in the race, he recorded a final three-furlong split in a 33-second range, winning by a commanding three-and-a-half-lengths margin over the runner-up, Libroadcast. The favorite, Born King, finished fifth.

In the subsequent Radio Tampa Hai Sansai Stakes for 3-Year-Olds (now the Hopeful Stakes), the competition was even tougher, but he went on to win, setting a record time for a 2-year-old over 2,000m. Jungle Pocket finished second by two and a half lengths, and Kurofune came in third—a high-level contest in which future G1 winners took the top three spots. Despite adopting a strategy known as "early move", or sensing the slow pace, he began to surge as early as the third turn, and was neck-and-neck for the lead by the fourth turn. He recorded the fastest final three furlongs of any horse in the field, at 34.1 seconds.^[13] After the race, jockey Kawachi was recorded saying, "I'm convinced this horse is in a league of its own." Trainer Nagahama highly praised Agnes Tachyon's performance, stating, "His racing style is better than his older brother's."^[13]

In the selection for Best 2-Year-Old Colt, a press vote where the winner of the Asahi Hai Stakes had historically been chosen, Agnes Tachyon garnered an exceptional 119 votes. However, was defeated by Asahi Hai winner Mejiro Bailey, who received 147 votes.^[14]

2001: 3-year-old season

Agnes Tachyon's owner had described him as having the potential to win the Triple Crown, and so he was entered into the Yayoi Sho, a major trial race for the Satsuki Sho, since both races are run over the same distance.^[15] On a heavy track, he won by five lengths over the second-place finisher, Born King, while the future Kikuka-shō winner, Manhattan Cafe, finished fourth.^[16]

Having performed so well in the qualifier race, and with Agnes Gold (who had been considered a top contender alongside Agnes Tachyon) withdrawn due to injury, he entered the Satsuki Sho as the overwhelming favorite.^[17] He started the race with a win-only betting support rate of 59.4%, the second-highest in history at the time. He won the race by easily kicking off in the final spurt from a good mid-pack position, in fourth or fifth place.^[18]

With this, he had won all four of his highly competitive races, and, since each victory had been achieved without any real threat, expectations were high for him to win the Triple Crown. However, on May 2, he developed superficial flexor tendonitis in his left front leg and had to withdraw from the Japanese Derby. Nagahama, who had expressed concern even while celebrating his Satsuki Sho victory, saying, "I'm happy, but I'm worried he might end up like Agnes Gold (who fractured his leg)"^[18] saw his fears become a reality.

He was subsequently sent to Shadai Farm for pasture rest, and following discussions among his trainer and owner, the decision was made to retire him. His retirement was announced to the public on August 29.^[19] A retirement ceremony was held at Hanshin Racecourse on September 30.^[18]