Niagara 74, Siena 62
SPRINGFIELD, Mass. (AP)
The Purple Eagles (19-12) built a nine-point lead with 5:51 to go until halftime, but the ninth-seeded Saints used a 12-4 spurt get within 32-31.
Marvin Jordan's trey opened the second half, then Mason scored seven straight points, capped by a three-point play with 17:19 left, to give Niagara an 11-point lead.
Siena (8-24) came back again with an 11-2 run to make it 44-42 with 12:19 remaining, but the Saints could get no closer.
The Purple Eagles, who swept Siena in the regular season, have won five of their past six games and are seeking their first MAAC title since 2007.
Evan Hymes and Rob Poole scored 14 points apiece and O.D. Anosike had 13 points and 10 rebounds for Siena.