Harbinger was crowned as the top performer of 2010 after the World Thoroughbred Rankings were released.
The Sir Michael Stoute-trained runner was awarded a mark of 135, putting him 6lb clear of next-best Blame despite the fact his career was curtailed by injury.
Harbinger was undefeated in four starts last term, culminating in an 11-length romp in the King George VI And Queen Elizabeth Stakes.
However, he did not race again after sustaining a leg injury following that Ascot demolition job, eventually being retired and sold to stud in Japan.
A mark of 135 puts him just 1lb behind Sea The Stars following his unbeaten run in 2009.
The British Horseracing Authority’s head of handicapping Phil Smith said: “I suspect Sea The Stars was a better horse than we were able to rate him, but 135 is absolutely sound. Harbinger is the highest-rated four-year-old since 1978 and Alleged, although some three-year-olds have been higher subsequently.”
Garry O’Gorman, the senior Irish handicapper, added: “His performance in the King George was astonishing, better than anything Sea The Stars produced, and I would not have had a problem had he been higher.”
Blame, who inflicted Zenyatta’s first career defeat when holding her by the narrowest of margins in the Breeders’ Cup Classic, is next best on 129, 1lb ahead of 2,000 Guineas victor Makfi, Derby hero Workforce and three-time American Grade One winner Quality Road.
Workforce was well beaten by Harbinger at Ascot but redeemed his reputation with victory in the Prix de l’Arc de Triomphe and shares the title of top three-year-old with Makfi.
Makfi was triumphant at Newmarket last May but suffered defeat by Canford Cliffs on his next start, although he is still rated 1lb higher than that rival.
Japanese-trained Arc second Nakayama Festa shares that rating of 127 while Aidan O’Brien’s Cape Blanco and Rip Van Winkle are both on 126.
They are joined at that level by dual Cox Plate winner So You Think, who is now part of the Ballydoyle set-up after leaving the care of Australian legend Bart Cummings.
O’Brien also had the top sprinter in Starspangledbanner (121) while record-breaking filly Goldikova is rated 125 following her third Breeders’ Cup Mile triumph.
Dewhurst hero Frankel and Prix Morny and Middle Park winner Dream Ahead have been assessed as the joint best juvenile colts on 126 while Cheveley Park victor Hooray is rated the leading two-year-old filly on 117.
For 3yos and up which raced between 1st January and 31st December 2010 and which were rated at 115 or above by the IFHA World Thoroughbred Rankings Conference – South African breds ranked:
J J The Jet Plane (122) put up a career best effort to take the Cathy Pacific Hong Kong Sprint (G1) at Sha Tin in December, just edging out Rocket Man (AUS) (121) and Sacred Kingdom (AUS) (121), and in the process became the highest rated South African-trained horse in WTR history, ahead of Pocket Power (121) in 2008
Lizards Desire- 121
Bold Silvano – 119
Irish Flame – 119
Pocket Power – 117
Big City Life – 116
Smart Banker – 116
Tropical Empire – 116
Blue Tiger – 115
Kapil – 115
Rudra – 115