| Horsename: | Topsider |
| Grandsire: | Nearctic |
| Dam: | Drumtop |
| Damsire: | Round Table |
| Sex: | Stallion |
| Foaled: | 1974 |
| Country: | United States |
| Color: | Bay |
| Breeder: | Paul Mellon & James B. Moseley |
| Owner: | Ardboe Stable |
| Trainer: | Thomas J. Kelly |
| Record: | 18: 8-3-0 |
| Earnings: | US$125,060 |
| Race: | Sport Page Handicap (1978) |
Topsider (1974–1992) was an American Thoroughbred racehorse. He was a bay son of the great Northern Dancer and the very speedy racing mare Drumtop. http://www.pedigreequery.com/topsider
Topsider won eight races from eighteen career starts, including the Sport Page Handicap at Aqueduct Racetrack in New York City.https://www.nytimes.com/1978/11/27/archives/sports-news-briefs-topsider-foils-bid-by-what-a-summer-bean.html In another of his wins he set a new track record of 1:14 2/5 for 6½ furlongs at Saratoga Race Course.
When his racing career was over, Topsider was sent to Claiborne Farm in Kentucky where became a significant sire whose offspring won more than $18 million in racing. http://nl.newsbank.com/nl-search/we/Archives?p_product=MH&s_site=miami&p_multi=MH&p_theme=realcities&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0EB347DDC0C05ED6&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM Among his best were two Champions: North Sider, the 1987 American Champion Older Female Horse, and Salse, a Champion Three-Year-Old in France. Topsider stood his entire career at Claiborne Farm and died there on October 18, 1992 as a result of a hernia in his diaphragm.