"We need to learn and grow up. We have two sophomores starting [Sean Bird and Noah Willerford] and these guys will be getting some significant minutes. The summer will be a learning time for us."
Castaneda finished with a team-high 16 points and Gardea added 11.
Perhaps the Golden Knights, who qualified for the playoffs last season after going 11-17 and 2-10 in league, will learn from their fourth-quarter struggles. After playing well throughout most of the first three quarters, the Golden Knights would go on to commit nine fourth-quarter turnovers.
The Golden Knights held a 35-26 lead entering the final stanza before Kennedy made a run to take a 38-37 advantage with 2:27 remaining.
On the ensuing possession, Castaneda made a three-pointer to give the Golden Knights a 40-38 lead with 1:41 left. Gardea then scored on a layup with 48 seconds left to make it 42-38.
Castaneda said the Golden Knights overlooked Kennedy in the fourth quarter.
"I think we just relaxed in the last quarter and we thought we had the game won," Castaneda said. "We learned that we need to keep competing and play defense until the end.
"That's the one lesson we have to learn — we need to compete the whole way."
Castaneda and Gardea opened the game by hitting back-to-back three-pointers to give the Golden Knights a 6-0 lead. Castaneda then made another three-pointer to extend St. Francis' lead to 11-2 with 6:59 left in the first quarter.
Gardea had a steal and converted it into a basket to give the Golden Knights a 19-5 advantage with 9:40 left in the second quarter. St. Francis held a 24-12 halftime lead.
Willerford made a three-pointer with 45 seconds remaining in the third quarter to give the Golden Knights a 35-25 lead. Willerford finished the contest with seven points.
"It's hard to simulate the season in the summer," O'Brien said. "When Emerson and Zack start to hit their shots, that can be a bad thing because everybody else starts to watch."