You cannot get this from the current API, no. The issue is that we generally see that information as more "editorial" in nature (because real-life opponents aren't specific to fantasy in any way), so we've always deferred to the part of the Yahoo! Sports team that works on the sports site for that sort of information. Of course, their services aren't publicly available, so it doesn't help you guys much. I'll file a bug to look into how we might fit this into our services, but I don't know if there's much chance of a quick turnaround on that.