Not done for the season, of course. The Saints have a very good team and an excellent chance to win their conference tournament, which is good news, because they're almost definitely going to need to.
Last night's loss to Niagara was a tourney-doomer for the Saints, and it's not hard to see why. Siena was a "maybe" for an at-large bid before last night's loss; their at-large chances largely rested on them finishing the regular season without adding to their four losses. A loss in the MAAC tournament after a perfect conference run would probably have been acceptable. But a loss to Niagara hurts the Saints, because, quite simply, Siena hasn't proven itself against top-notch competition. The Saints squandered their three chances to get wins against teams in the top 50 of the RPI -- with losses to Temple, Northern Iowa and Georgia Tech -- and despite a top 35 RPI, have zero quality wins to speak of.
This is why it's tough to be a mid-major. Ask UNI, or Butler. These teams can be ostensibly talented enough to get in the NCAA tournament, but one or two slip-ups in the regular season -- the kind of thing even elite teams like Kansas do from time to time -- and we automatically remove them from tournament consideration. Plus, few "quality" major teams will play these teams on neutral courts or at their own arenas, so their only opportunities to get quality wins come on the road. Siena is a classic example, and it's borderline unfair.
Then again, there are those that still think Siena can make the NCAA tournament as an at-large. It's not impossible. More likely, though, is that Siena has to win it from March 4-8, when the MAAC tournament convenes in Albany, NY. It's a bummer. It'd be awesome to have Siena in the tournament again. But this is how things work.