The Relative Unimportance of Beowulf

I think it's interesting that we didn't meet or hear about Beowulf until the last few pages of the book, whereas a large part of it was focused on Unferth. Initially, Grendel has a "vision" of Beowulf as a super strong being with fiery wings before he realizes that he is only a man. But then Beowulf's whispering terrifies Grendel, and he rips off his arm, all in three pages.

In the original epic, obviously Beowulf was a much more important entity - the killer of the violent monster. So why did Grendel notice Unferth, but not Beowulf? What is the significance of Gardner leaving Beowulf out? If you're familiar with the original epic, how does it compare?