The 34-year-old, who was known as “El Gallo” was in the ring participating in a ‘recortador' when amateurs dodge and swerve a charging bull.
The blacksmith from Navalmanzano in Segovia was said to be an experienced ‘bull dodger' who had leapt in front of bulls hundreds of times.
But on Saturday morning after the bull run he slipped at an inopportune moment and was caught on the horns of the bull.
He was gored through the thigh and chest and died after being transferred from the ring to a hospital in Valladollid.
Friends posted a video tribute to El Gallo on YouTube.
Celebrations in La Parilla were suspended following the death and two days of mourning declared.
His hometown of Navalmanzano also declared two official days of mourning where the mayor Pablo Ángel Torrego described Otero as "a beloved son of the town".
It was the first fatal goring of 2016. Last year was one of the bloodiest seasons in recent memory whebn at least 13 people were fatally gored during taurine festivals.