What lies beneath: Under Vermeer's 'Girl with the Red Hat' may be the artist's only existing male portrait

From The Art Newspaper:

Three years ago it was revealed that the panel of Girl with the Red Hat (around 1664-69) at the National Gallery of Art (NGA) in Washington, DC, was overpainted on top of an earlier composition, a rather conventional portrait of a man (above). 

This earlier research suggested that the male figure was not the work of Vermeer, but by an unidentified artist. 

Its brushwork was loose, unlike Vermeer’s refined style. 

But more recent studies, using the latest imaging techniques, show that Vermeer’s initial paintwork was generally looser and done quickly at the underpainting stage. 

The NGA specialists therefore now argue that the male portrait could be his own work; this “has not yet been proven or denied.”