I must admit that working out an answer to this question was somewhat challenging. In Digenis Akrites, the amazon Maximo fights Digenis purely on the insistence of her relative Philopappos, who intended to abduct Digenis' wife,Evdokia. Maximo falls into the trap (the suggestion is that she would never willingly have had anything to do with an attack on Digenes).The author writes:
Thus having spoken old man Philopappos
Made Maximo in all respects submissive—
For woman's mind is easily deceived.
The battle between Digenis and Maximo is described in the text from a first person point of view.
In the battlefield Maximo realises she has been tricked into fighting a solitary man without an army of his own. She finds it unethical to attack him with an army and resolves to fight Digenis on her own.This is what she tells Philopappos:
"You thrice accurst old man," she answered him,
"So me and my people you troubled for one man,
To whom I will cross alone, boasting with God's help
I will bring back his head, not needing you?"
In the battle that follows Digenis emerges the victor and Maximo expects to be killed. She pleads for her life and Digenis spares her for her "wondrous beauty" as is quoted in the question.She thanks him for his mercy, blesses him for his valour, and asks that they may meet again in the morning in single combat.
One more request, that by it you may know
More strictly my experience in war:
Bid me to go away and mount my horse,
And in the morning I will come to this place,
That we may singly fight, none present with us,
And you shall see, good friend, my bravery."
"With joy, O Maximo," I said to her,
"Go where you will, and you shall find me here."
Maximo wishes to redeem herself.Is there any indication that she wishes to throw the duel? None at all. Why on earth would she challenge him then?
As for the second duel, there is nothing at stake. Digenis has spared Maximo once and is looking forward to the second duel "with joy".The antagonists apparently wish to pit their skills against each other:
And when we were come near we both embraced
Greeting each other lovingly, as was fair.
Maximo is disarmed which apparently implied defeat.She was seized by great fear and is the first one to bring up the topic of intercourse, albeit within the framework of marriage. This makes rape seem somewhat far-fetched. There is nothing to indicate that Maximo was forced into having sex.
I am a virgin still by none seduced.
You alone have conquered, you shall win me all;
And have me helpmate too against your foes."
Digenis undoubtedly finds Maximou attractive:
My soul was wounded, she was beautiful.
They proceed to have sex.
A better example of rape (and of male chauvinism) in a similar situation can be found in Irish mythology (the duel between Aoife and Cu Chulainn). Here, Aoife has to choose between death and Cu Chulainn. I'm not sure the situation is so grave for Maximo here. Her defeat did not imply offering herself to the victor as it did for Aoife.