1 Chronicles 19:11

And the rest of the people he delivered unto the hand of Abishai his brother, and they set themselves in array against the children of Ammon.

Cross-reference

1 Chronicles 11:20 identifies Abishai as Joab's brother and a mighty warrior, the same person sent against the Ammonites here.

1 Chronicles 18:12 records Abishai's victory over Edom, another deed of the same commander mentioned in this verse.