Judges 4:21 describes Jael killed Sisera while he was sleeping:
But Jael, Heber's wife, picked up a tent peg and a hammer and went quietly to him while he lay fast asleep, exhausted. She drove the peg through his temple into the ground, and he died.
This seems to be a quick and clean execution. Later Deborah sang about this event in Judges 5
25 He [Sisera] asked for water, and she [Jael] gave him milk;
in a bowl fit for nobles she brought him curdled milk.
26Her hand reached for the tent peg,
her right hand for the workman’s hammer.
She struck Sisera, she crushed his head,
she shattered and pierced his temple.
27At her feet he sank,
he fell; there he lay.
At her feet he sank, he fell;
where he sank, there he fell—dead.
In the song, there is more detail. Was Sisera able to get up after the initial blow? Or is this some poetic add-on to spice up the event? When did the "he fell" happen?