2 Samuel 2:16-20

And they caught every one his fellow by the head, and thrust his sword in his fellow’s side; so they fell down together: wherefore that place was called Helkath-hazzurim, which is in Gibeon.

And there was a very sore battle that day; and Abner was beaten, and the men of Israel, before the servants of David.

And there were three sons of Zeruiah there, Joab, and Abishai, and Asahel: and Asahel was as light of foot as a wild roe.

And Asahel pursued after Abner; and in going he turned not to the right hand nor to the left from following Abner.

Then Abner looked behind him, and said, Art thou Asahel? And he answered, I am.