Rainbow Line

Rainbow Line began his racing career by running second in a contest for previously unraced juveniles over 1800 metres at Sapporo Racecourse on 2 August 2015. After finishing runner up over the same course and distance two weeks later he opened his winning account in a maiden race (again over 1800 metres at Sapporo) on 30 August as he won from Tizona and seven others. After a two-month break the colt was stepped up in class for the Listed Hagi Stakes at Kyoto Racecourse and finished third behind Black Spinel and Smart Odin.[7] Despite he was promoted again to contest the Grade 3 Tokyo Sports Hai Nisai Stakes at Tokyo Racecourse on 23 November in which he started a 36/1 outsider and came home ninth of the eleven runners behind Smart Odin.[8] On his final start of the year Rainbow Line was dropped back in distance for the Sanryo Sho over 1600 metres at Hanshin Racecourse on 27 December and won narrowly from Sunrise Couronne.[7]

Rainbow Line's trainer Hidekazu Asami

Two weeks after his last start of 2015, Rainbow Line began his second campaign in the Shinzan Kinen at Kyoto and finished sixth of the eighteen runners behind Logi Cry. On 27 February at Hanshin the colt contested the Grade 3 Arlington Cup over 1600 metres on firm ground and started the 5.8/1 fourth choice in the betting behind Urban Kid, Ball Lightning (Keio Hai Nisai Stakes) and Hiruno Magellan. Ridden by Mirco Demuro he raced towards the rear of the field before moving up on the wide outside on the final turn and staying on strongly in the straight. In a "blanket finish" which saw the first five finishers separated by less than a half a length he prevailed by a nose from Dantsu Prius.[9]

The Grade 2 New Zealand Trophy at Nakayama Racecourse on 9 April saw another very tight finish and Rainbow Line was beaten less than a length as he finished fifth behind Dantsu Prius. On 8 May the colt was stepped up to Grade 1 class for the first time to contest the NHK Mile Cup at Tokyo and started a 40/1 outsider. Ridden by Yuichi Fukunaga he exceeded expectations as he stayed on strongly in the straight to finish a close third behind Major Emblem and Lord Quest.[10] He was then moved up in distance for the Tokyo Yushun three weeks later in which he started at odds of 154/1 and came home eighth of the eighteen runners behind Makahiki.

After a break of two and a half months Rainbow Line returned to the track in August when he was matched against older horses for the first time in the Grade 2 Sapporo Kinen. With Fukunaga in the saddle he came from the rear of the field with a strong late run to take third place behind the five-year-olds Neorealism and Maurice. In October the colt was moved up again in trip for the Kikuka Sho over 3000 metres at Kyoto and started a 23.9/1 outsider in an eighteen-runner field. After racing towards the rear for most of the way he produced an "impressive late charge" to take second place behind Satono Diamond with Air Spinel and Dee Majesty finishing close behind in third and fourth.[11] On his final run of the season in the Japan Cup on 27 October Rainbow Line produced his customary late run from the rear of the field to come home sixth of the seventeen starters, four lengths behind the winner Kitasan Black.

In the 2016 edition of the World's Best Racehorse Rankings Rainbow Line was given a rating of 116, making him the 158th best racehorse in the world.[12]

Rainbow Line began his third season by running fourth behind Sciacchetra in the Nikkei Sho over 2500 metres at Nakayama on 25 March. Five weeks later he ran poorly in the spring edition of the Tenno Sho over 3200 metres at Kyoto as he finished twelfth of the seventeen runners behind Kitasan Black. After this race Yasunari Iwata took over the ride and partnered the horse in all of his subsequent starts. In the Takarazuka Kinen in June the colt produced a better effort as he came home fifth of the eleven runners behind Satono Crown.[7]

After a break of more than five months Rainbow Line returned in the autumn edition of the Tenno Sho in which he started a 58.6/1 outsider and produced a strong late run to take third place behind Kitasan Black and Satono Crown.[13] IN November the colt contested his second Japan Cup and repeated his 2017 result as he finished sixth behind Cheval Grand having turned into the straight last of the seventeen runners. He ended the year by running eighth behind Kitasan Black in the Arima Kinen at Nakayama on 24 December.

In the 2017 edition of the World's Best Racehorse Rankings Rainbow Line was given a rating of 118, making him the 90th best racehorse in the world.[14]

Yasunari Iwata, who rode Rainbow Line in his last six races

On 18 March 2018 Rainbow Line began his fourth campaign in the Hanshin Daishoten over 3000 metres. He started the 4.6/1 third choice in the betting behind Clincher (Kyoto Kinen) and Albert (Stayers Stakes) in an eleven-runner field which also included Satono Chronicle (Challenge Cup) and Curren Mirotic (Kinko Sho). After being restrained towards the rear as usual, Rainbow Line moved up on the outside on the final turn, hit the front approaching the last 200 metres and recorded his first win for more than two years as he came home a length and a quarter in front of Satono Chronicle with Clincher in third place.[15]

At Kyoto six weeks later Rainbow Line made his second attempt to win the spring edition of the Tenno Sho and was made the 5/1 second favourite behind Cheval Grand. Clincher, Satono Chronicle, Albert and Curren Mirotic were again in opposition while the other eleven contenders included Ganko (Nikkei Sho), Chestnut Coat, Tosen Basil, Mikki Rocket (Nikkei Shinshun Hai) and Smart Layer (Hanshin Himba Stakes). The outsider Yamakatsu Raiden set the early pace with Rainbow Line settled well back in the field. Cheval Grand gained the advantage in the straight but Rainbow Line threaded his way through field after being switched to the inside by Iwata, caught the favourite in the final strides and won by a neck.[16] Immediately after the race the horse was found to be lame, having sustained an injury to his right foreleg and was taken receive treatment at a veterinary facility rather than taking part in the victory ceremony. Iwata said "While our rivals were making early moves in the backstretch, my mount waited patiently, and I knew he had the needed late kick to reach the front before the wire. I'm worried about the horse. I just hope he’ll be able to run in the next race" while Hidekazu Asami commented "It's great that he was able to win but I'm concerned about his condition. I hope to give him the best care as possible".[17]

Rainbow Line was unable to return to the track following his injury and was retired from racing at the end of the year.

In the 2018 World's Best Racehorse Rankings, Rainbow Line was again given a rating of 118, making him 78th best horse in the world.[18]