Beljan grabbed a 3-stroke lead Friday with an 8-under 64 despite battling a rapid heart rate and struggling with shortness of breath.
After spending the night in a hospital, Beljan returned Saturday with only 1 hour of sleep and responded with a 71, good enough for a 2-shot advantage at 13-under 203 after 54 holes.
Beljan, who came into the event seeking just to retain his PGA Tour card, will go for his first tour title Sunday.
Ending Round 3 in a three-way tie for second place were Brian Gay and Josh Teater -- each of whom fired 5-under 67s -- and Charlie Wi (70), who forfeited the lead with a pair of bogeys on the final two holes.
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