How to extract date out of this filenames

I have filenames

filenameA_fg_MMDDYY.tar.gz
filenameASPQ_fg_MMDDYY.tar.gz
filenameAFTOPHYYINGH_fg_MMDDYY.tar.gz
filenameAGHYSW_fg_MMDDYY.tar.gz
Is there a way I can extract the date out of these filenames?
Thanks in advance

echo $filename | awk -F"[_.]" '{print $3}'

Thanks.It worked anchal