It was last summer, after Encino Crespi held a three-point lead over Chino Hills with four minutes to go in a summer league game, that Coach Russell White knew how good a team he might have.
Then came Saturday's 66-63 overtime victory over Redondo in the Division I Southern California Regional final at the Pyramid.
"I can say we've reached that potential," he said.
The Celts (32-4) rallied from a nine-point halftime deficit to earn a spot in Thursday's 8 p.m. Division I state championship game against Berkeley at Sleep Train Arena.
Sophomore Brandon Williams, who missed a layup at the end of regulation that could have won the game, delivered a three-point play with 37.7 seconds left, and sophomore Taj Regans made four consecutive free throws in the final seconds to secure the victory.
De'Anthony Melton finished with 21 points and 15 rebounds. Williams had 15 points and Regans 10.
Leland Green led Redondo with 15 points and Ryse Williams had 13. Redondo lost Green and Elijah Nesbit to five fouls, hurting the Sea Hawks' chances in overtime.
"That was a war, plain and simple," White said. "It was our defense that ultimately won it for us."
Long Beach Poly will get the chance to win its first state title since 1984 after relying on the aggressive play of Drew Buggs to defeat Riverside North, 61-54.
Buggs, not close to 100% after suffering a knee injury last November, scored 20 points and was consistently in attack mode. Zafir Williams added 13 points and 16 rebounds for the Jackrabbits (24-10), who will play San Mateo Serra in next Saturday's 4 p.m. final at Sleep Train Arena.
"For him to come back and play for what he's gone through, you have to give him all the credit in the world," Coach Shelton Diggs said. "He has the desire to help this school try to get a championship."
Poly had to overcome a 27-point, 16-rebound performance from North's 6-foot-6 Christian Gray to avenge a loss to the Huskies in the Southern Section 1AA final.
Buggs might not be able to jump very high with his right knee in a brace, but his court presence is pretty invaluable.
"He had a tremendous will to win," North Coach Mike Bartee said.
Said Buggs: "I felt I let the team down in the CIF championship game and needed to step up. I tried to be aggressive and open up opportunities for the rest of the team."
Freshman Cassius Stanley scored 22 points and had nine rebounds to help Studio City Harvard-Westlake defeat Calabasas Viewpoint, 52-39, at Colony. Harvard-Westlake will play Salinas Palms on Saturday at noon.
Senior guard Adam Amanuel scored 28 points, making 11 of 14 shots, to lead Playa del Rey St. Bernard past Temecula Rancho Christian, 67-61.
Isaiah Mobley led Rancho Christian with 20 points. St. Bernard is 19-16 and will play Alameda St. Joseph Notre Dame in Thursday's noon final at Sleep Train Arena.
Follow Eric Sondheimer on Twitter @LATSondheimer