Associated Press
Experts at Prado museum in Madrid, Spain, says "Colossus" is not the work of Goya.

MADRID, Spain — For years Spain's famed Prado museum had its suspicions about one of its most prized Goyas. Now the museum says it is certain the painting is not by the 18th-century master.

The Prado's announcement last week about the "Colossus," a large oil painting depicting the torso of a giant bursting through the clouds as he marches above a terrified village, is causing a furor among experts, some of whom still believe the painting is genuine.

Francisco de Goya y Lucientes' "Colossus" has always been one of the Prado's major attractions and a highlight of his series on Spain's war against Napoleon, whose troops invaded in 1808.

Doubts about its authenticity began to surface in the early 1990s, and grew in April when the museum unexpectedly excluded the painting from its blockbuster show "Goya in Times of War."

Then, last week, Manuela Mena, a Goya expert and the Prado's chief 18th century art conservationist, told Spain's El Pais newspaper that the painting is filled with stylistic points that don't square up to Goya's talent.

The giant's raised left arm is too crudely painted for such an expert on anatomy as Goya, she said, and his expertise in drawing bulls and other animals would never have let him depict them as they are in the painting.

"The painting is not by Goya's hand," she said. "Goya would never have painted it like that."

The museum, which continues to display the work in its Goya rooms, says fresh studies indicate the "Colossus" may be the work of a minor painter, Asensio Julia, a pupil and a workshop assistant of Goya's. One of the most significant findings, it says, are what appear to be Julia's initials at the bottom of the painting.

"The museum is certain it is not a Goya. That's for sure. What's not so clear is who actually painted it," a Prado spokeswoman told The Associated Press. She was speaking on condition of anonymity in keeping with museum policy.

Others disagree.

"I think it's a Goya," Nigel Glendinning, a leading British art historian and Goya expert, said.

Glendinning dismissed Mena's argument about the crude style of the work, saying Goya rarely went for specific details in his paintings, often preferring broad and rough brush strokes.

Glendinning pointed to other evidence as well, including a record that a work by the same name was in Goya's house in 1812. That painting, he maintains, turned up in the inventory of an aristocratic family in Madrid in 1874, and a descendant turned it over to the Prado in 1930.

"It's easy to show that the painting in that inventory in 1874 is the painting now in the Prado because the person who gave it the Prado in 1930 was a descendant of the same family," said Glendinning.

Even some people more directly linked to the Prado are not ready to write the painting off.

"It's going to be difficult for me to accept a change in authorship," honorary Prado director Jose Manuel Pita Andrade told daily ABC. "We're talking about one of Goya's most extraordinary works,"

The Prado, which holds the world's biggest collection of Goyas and considers itself the leading authority on the artist, says an investigation into who actually painted Colossus is not expected to wind up before the end of this year.

Jonathan Brown, a New York University art history professor and Prado expert, told AP the brouhaha is simply another example of the unending problem of authorship in old masters' works.

"Every field of Western art has its problem paintings," he said. "This is happening with Caravaggios all the time."