Summing (April 16, 1978 – October 10, 2008) was an Americanthoroughbredracehorse andsire.

Summing was a bay horse bred in Kentucky by his owner Charles T. Wilson Jr. He was sired byVerbatim, a leading dirt performer whose wins included the 1969Whitney Stakes. The best of his other progeny includedAlphabatim andPrincess Rooney. Summing's dam Sumatra was a high-class racemare whose wins included a division of theSanta Ysabel Stakes.^[2]

Until the detection of a blood infection, Summing performed so poorly that he was dropped fromgraded stakes races and entered in an allowance race. Once the infection was found, he was unable to compete in theKentucky Derby and thePreakness Stakes, although two weeks before the Belmont he was well enough to win thePennsylvania Derby.

Trained byLuis Barrera, brother ofAmerican Hall of Famethoroughbredracehorse trainerLaz Barrera, Summing is best known for his upset overU.S. Champion 3-Yr-Old ColtPleasant Colony in theBelmont Stakes withGeorge Martens aboard. He won the race in a time of 2:29, spoiling Pleasant Colony's bid for theTriple Crown, as Pleasant Colony ran wide in the turn and placed third, behindHighland Blade.^[3]

In the fall, Summing won thePegasus Stakes, then finished second in theSuper Derby.

Summing was retired to Jonabell Farm, where he stood at stud until from 1982 to 1991. He was then sent to Getaway Farm inCalifornia. Summing was pensioned from study duties in September 2003 due to declining fertility^[4] and stood at the farm until he died in his sleep of natural causes at 30 years old in October, 2008.

Hisgraded stakes race progeny includeEpitome, Summer Matinee, and Matthews Keep.

• Summing wasinbred 4 × 4 to Nasrullah, meaning that this stallion appears twice in the fourth generation of his pedigree.

• 1978 racehorse births
• 2008 racehorse deaths
• Racehorses bred in Kentucky
• Racehorses trained in the United States
• Belmont Stakes winners
• Thoroughbred family 1-g

• Articles with short description
• Short description is different from Wikidata