User exit Mat doc number in BSEG-SGTXT

Hi, guys.

Are there any user exits to capture the material doc number and transfer to BSEG-SGTXT?

I checked user exit MBCF0002 does it on FI side. But I am having a hard time capturing MBLNR. Found Badi MB_DOCUMENT_BEFORE_UPDATE, but this is called after exit MBCF0002.

I tried BTE's in FIBF t-code, but I need the exit to export MBLNR to memory for later usage in FI interface.

I tried substitution, GGB1, but it doesn't work. Since AWKEY contains mat doc + year, but I think BKPF-AWKEY has no value yet at some point until the FI doc is saved.

I hope you guys can help.

Thanks.

Regards,

Rey