The Blue Devils (9-1, 5-0 Northeast Conference) are ranked No. 20 in the STATS FCS 25, but had to scramble for the win.
The Red Flash (4-6, 2-4) outgained CCSU 434-367 in total offense, ran a dozen more plays, and led 31-28 lead with a little more than four minutes left in the game.
Jason Brown, who completed 35 of 52 for 355 yards, found Ra'Shaun He for a 31-yard TD and the late lead.
Winchester then directed the Blue Devils down to the 2-yard line with five seconds on the clock, setting up Joe Zoppi's 19-yard field goal that sent the game into overtime.
It was St. Francis' third OT in six Northeast Conference games this season, and the Red Flash have yet to win one.
In overtime, CCSU had first possession and, with two completions, Winchester had the Blue Devils up by seven.
St. Francis' answering drive stalled at fourth-and-5 when Brown was sacked by Mike Mushaw for a 12-yard loss.
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