Genesis 18.10
Septuagint

eipe de, epanastrefwn hxw proV se 
kata ton kairon touton
eiV wraV, kai exei uion Sarra h gunh sou

New Testament - Romans 9.9

epaggeliaV gar o logoV outoV: 
kata ton kairon touton
eleusomai kai estai th Sarra uioV

Septuagint

And he said, I will return and come to thee according to this period seasonably, and Sarrha thy wife shall have a son

New Testament

For this is the word of promise, According to this season will I come, and Sarah shall have a son
 

Masoretic Text

And he said, I will certainly return unto thee when the season cometh round; and, lo, Sarah thy wife shall have a son

Comments:  The NT, LXX and MT agree.