Gunnevera is a chestnut colt bred in Kentucky by Brandywine Farm in partnership with Stephen Upchurch.

[6] She was bought in 2005 by Brandywine as a ten-year-old broodmare for a mere $13,000, the low price due to the lack of success of her first four foals on the racetrack.

[10] Sano was a highly successful horse trainer in Venezuela who fled to United States after having been kidnapped twice.

[9] Following the sale, Gunnevera was sent to Julio Rada's Altamira Stable in Ocala, Florida to be broken in, and was sent back to Sano's barn when it came time for him to make his racing debut.

[12] Gunnevera finished fifth behind eventual two-year-old champion Classic Empire in the Gr.I Breeders' Futurity Stakes.

In his final start as a juvenile, he found the winner's circle in the Delta Downs Jackpot Stakes.

Gunnevera then won the Fountain of Youth in his next start, defeating multiple Gr.I winner Practical Joke, Three Rules, and Irish War Cry.

In his next start, the 2017 Preakness Stakes, Gunnevera was ridden by Mike E. Smith after Castellano opted to ride Cloud Computing, who won the race.

Gunnevera finished fifth[15][16] but came out of the race with bleeding in his left hind leg and did not start in the Belmont Stakes.

[17] After being bumped hard at the start, Gunnevera dropped well back for the first half mile before beginning a sustained run on the backstretch.

He circled wide on the final turn and moved into contention in mid-stretch while bearing in and bumping with Irap, who finished third.