York guard David Cohn admitted that, with 27 seconds left and the Dukes trailing Conant 29-28, "I was shaking going to the free throw line."
Cohn received a friendly bounce on the first attempt, then also made the second.
Moments later he deflected D'Angelo McBride's pass out of bounds with 4.6 left.
The Cougars' Joey Ranallo inbounded the ball to Mark Monti, who passed back to Ranallo. The junior guard put up a lefthanded layup that was slightly tipped by the Dukes' Stanley Roberts. The shot fell off the rim, denying Conant a chance to win its fifth Jack Tosh Holiday Classic tournament victory Saturday night in Elmhurst.
Instead, York broke a 32-year tournament drought in winning 30-29.
"We had the opportunity to win the game," said Coant coach Tom McCormack . "They are a good team, and they played well on their floor."
Conant, now 10-6 after its eight-game winning strreak was snapped, led only once, at 29-28 following Kevin Schimel's 3-point basket with 2:40 to play.
Ranallo had chance with 1:15 left to increase the lead but the first of the one-and-one bonus attempt fell short. Justin Kurash grabbed his seventh rebound to give the ball back to the Dukes (12-3).
Cohn was fouled with :44 left and missed the front end of a one-and-bonus. Frank Toohey of York tipped the ball back and Cohn recovered for the Dukes. That led to Cohn's clutch free throw makes with :27 left.
"It was great to win the tournament for the first time in 32 years," said Cohn. "It was a rewarding win for the team. When I went to the free throw line, I just had to block out that I had missed the first one."
York coach Vince Doran praised Cohn for his defense.
"He's improved his defense this year, " said Doran. "We challenged him in practice to improve his defense. He came up with a good defensive play late in the game . We like to run, and when we broke out to a early lead (8-1), I thought we might get the score into the 50s. I knew that Conant would come back and battle us."
York built a 21-13 lead at halftime, but Conant bounced back to hold the Dukes to 9 second-half points.
Cohn was held to just 9 points by the Cougars D'Angelo McBride after he scored 7 in the first quarter. Kurash added 7 points for York, which shot 11 of 35 for 31 percent.
Robert Hudson had 8 point to lead the Cougars. Kevin Schimel had 6 points. The Cougars shot 30 percent, hitting 11 of 37 shots.
"We've been able to establish our identity as a defensive team," said McCormack. "Now we have to get better with our offense. McBride and Schimel played really good defense for us in the tournament. They gave us some turnovers in the second half (10) but we needed to create more offense from the defensive rebounds and the turnovers."
Riverside-Brookfield 78, Waubonsie Valley 67: The Warriors had a rough day, losing the third-place contest to the Bulldogs. Earlier in the day Waubonsie was beaten by the host Dukes in the other morning semifinal.
Jared Brownridge led the Warriors (8-6) with 19 points. Bryan Jefferson scored 12 and Nick Karkazis 11.
Tied at 20 after the first quarter, the Bulldogs outscored the Warriors 21-12 in the second quarter for a 41-32 lead and never again trailed.
Center Miki Ljuboja scored 20 of his 33 points in the first half for R-B. Domanta Henry added 13 points and Jack VanderMerkt 12.
Conant 45, Riverside-Brookfield 38 (OT): Tied at 31 at the end of regulation, the Cougars scored the first few times they had the ball in the overtime to hold off the Bulldogs in the morning semifinal.
Robert Hudson (11 points) hit a 3-point basket to the the game at 31 with :42 left. Riverside-Brookfield took the last shot in regulation with :03 left but missed.
Joey Ranallo led Conant with 13 points and D'Angelo McBride scored 10.