Borges on Tolkien

So far as I know, Jorge Luis Borges (1899-1986), Argentinian author of such magisterial fantasy stories as "The Aleph" and "Tlön, Uqbar, Orbis Tertius," mentioned Tolkien only twice--and not favorably. I wondered why, for it would have seemed, knowing Borges's other interests (from Anglo-Saxon to Lewis Carroll--Borges was especially well-read in British literature), that he might have been a fan.