Binghamton rallied from a 14-point deficit and had taken its first lead on Willie Rodriguez's two free throws with 13.8 seconds left. But with the Mountaineers (4-6) working for a final shot, Smeathers, passing the ball, was fouled by Justin McFadden.
Chris Martin scored 18 points, Kristijan Krajina 14 and Junior Robinson 12 for Mount St. Mary's, which prevailed despite shooting 43.1 percent while the Bearcats shot 56.8. Both had 25 field goals but the Mountaineers had a 16-8 advantage on the offensive boards and took advantage of 20 turnovers.
Rodriguez finished with 25 points and Dusan Perovic 15 for Binghamton, which claims to have the least experienced roster in nation with a combined 10 years of collegiate experience. The Bears (1-13) have lost 11 straight.