Gary:
I too am not familiar with current Esri/SAP interfaces.
As I recall, this is a pretty new alliance, 2013 UC perhaps?
Esri Partners | SAP | Overview
At my prior job, we built a custom ArcMap tool that picked up selected features and passed them to a custom SAP BAPI via the SAP .NET connector. I believe it then called up the SAP work order module to finish things off.
It was a bit of a PIA truthfully that required some false starts.
The biggest issue was the SAP .NET connector was really old (required VS 2003 I think, in 2010 or so?)
A new connector came out just after we finished the upgrade of the tool from ArcGIS 9.3 to 10.0
I was managing the programmer so my involvement was only skin deep.
These days I would first look for an API from SAP & Esri.
If that failed, then I'd look at doing this in Python as it appears SAP has Python interfaces available in various ways.
RFC, etc... Some folks talk about building a web service that you then consume...
Python / ABAP Stack | SCN
I believe a lot of how you go depends on your SAP implementation.
And of course your ArcServer implementation.
I do think the one thing you do not ever want to do with SAP is directly manipulate your database tables.
You always want to work through the abstracted SAP interfaces.
A behemoth like SAP does not move very quickly but one might think that two years later, you will be able to find tools that simplify a lot of this.
Best of luck.