Spanish matador Jose Tomas, one of the world’s most famous and dramatic bullfighters, was severely gored by a half-ton bull in a Mexican arena and is in critical condition, doctors said Sunday.

Tomas is expected to survive after undergoing more than three hours of emergency surgery overnight following his injury Saturday afternoon.

“There has been slight improvement, but he’s still in grave condition,” Dr. Geronimo Aguayo said in a statement released by Tomas’ hospital in the central Mexican city of Aguascalientes.

The bull, named Navegante, gored Tomas in the groin and lifted him in the air before a horrified crowd during a corrida at the Monumental bullring in Aguascalientes. The attack left a 6-inch-long gash in Tomas’ left thigh, severing the artery. He lost a large amount of blood.

“The danger of death has passed, but with these types of gorings, anything can happen,” another of his doctors, Enrique Gonzalez Careaga, told reporters.

Tomas, 34, who was the subject of a Times story in 2007, has survived more than a dozen similar attacks, the first, in 1994, at this very same venue. Tomas hails from a small town near Madrid in the heart of Spain’s bull-rearing ranchland, but much of his early career evolved in Mexico.

To aficionados, Tomas is a mesmerizing figure in the bullring, an artful and daring master of the ritual that is part of Spain’s national patrimony and popular in many parts of Latin America.

He almost singlehandedly revived the spectacle in Spain, where it had been declining in audience for years until Tomas came out of an early retirement in 2007. He thrills spectators by seemingly putting himself in repeated danger, challenging the beast with calm command and precise choreography.

In Barcelona, Spain, where Tomas has been filling the bullring to capacity in recent seasons, the crowd on opening day of the 2010 circuit Sunday observed a minute of silence in Tomas’ honor.

Assuming he recovers fully, it is not clear how long Tomas would be out of commission.

As he lay bleeding profusely Saturday in the Aguascalientes stadium, a call went out on loudspeakers pleading for urgent blood donations. Scores of people rushed to donate.

wilkinson@latimes.com