Complex sentence: In 2008, the Museo del Prado announced that there were reasons to suspect that the painting was actually painted by Asensio Juliá, an apprentice of Goya's, as the painting contained the initials "AJ" in the lower left hand corner of the canvas.
Split into simpler sentences: In 2008, the Prado Museum announced that there were reasons to suspect that the painting was actually painted by Asensio Juliá, an apprentice of Goya's. The painting contains the initials "AJ" in the lower left hand side of the canvas.