Australian superstar Black Caviar is officially the world's best racehorse following the release of the first international rankings for 2011.Her victory in the Group One Newmarket Handicap (1200m) at Flemington on March 12 has been rated by the the International Federations of Horse Authorities (IFHA) as the best performance by a thoroughbred anywhere in the world for the six-month period from October 1, 2010 to March 27 this year.The Newmarket triumph took Black Caviar's unbeaten streak to 10

Australian superstar Black Caviar is officially the world's best racehorse following the release of the first international rankings for 2011.

Her victory in the Group One Newmarket Handicap (1200m) at Flemington on March 12 has been rated by the the International Federations of Horse Authorities (IFHA) as the best performance by a thoroughbred anywhere in the world for the six-month period from October 1, 2010 to March 27 this year.

The Newmarket triumph took Black Caviar's unbeaten streak to 10 and earned her a rating of 130.

The IFHA began its World Thoroughbred Rankings (WTR) in 2002 taking in the performances of horses in all global racing jurisdictions.

Black Caviar is now the highest-rated sprinter since the WTR started, eclipsing Oasis Dream (125 in 2003), and became the first sprinter to head the WTR, the first Australian horse to head the WTR and the highest-rated Australian horse, eclipsing So You Think (126 in 2010).

The four-year-old is also the equal highest-rated mare, joining French champion Goldikova (130 in 2009).

Greg Carpenter, chairman of the ANZ Classifications Committee and Australia's representative on the WTR committee, said the result was monumental.

"This is a landmark day for Australian racing with Black Caviar heading the list of the top 50 active thoroughbred racehorses in the world," Carpenter said.

"Winners at the Dubai World Cup meeting, US Breeders' Cup meeting, Hong Kong International meeting and the Arc de Triomphe have all been rated inferior to Black Caviar.

"That helps put into context the enormity of her achievement in winning the Newmarket Handicap and indeed her amazing sprinting performances over the past six months.

"It is particularly pleasing that she has broken ground for sprinters in the World Thoroughbred Rankings and showcased the growing strength of Australian racing on the world stage."

USA Breeders' Classic (dirt) winner Blame, the only horse to defeat glamour mare Zenyatta, isthe second-ranked horse on 129, with Arc de Triomphe winner Workforce (UK) and runner-up Nakayama Festa (Japan) next best on 128 and 127 respectively.

Rounding out the top five is former Australian superstar, the now Irish-trained dual Cox Plate winner So You Think who achieved a rating of 126 for his victories in the Group One Mackinnon Stakes (2000m) and Group One Yalumba Stakes (2000m) during the Melbourne spring.

Australian-trained Hay List, Whobegotyou and Zipping are equal 30th with a rating of 120, while Shocking is equal 44th following his win in the Australian Cup.

Australian-bred Singapore star Rocket Man improved his rating to 122 with his victory in last weekend's Group One Golden Shaheen (1200m) in Dubai and is ranked 11th and sits alongside South Africa's JJ The Jet Plane as the equal second-highest sprinter.

Black Caviar took her record to 11 wins from 11 starts when she claimed her fourth straight Group One at Moonee Valley last Friday night in the William Reid Stakes (1200m).

Her next appearance will be in the Group One TJ Smith Stakes (1200m) at Randwick on April 9.