Bagley, the No. 1 player in the Class of 2018, scored 28 points, including 11 of his team’s first 13. Martin, an Arizona State commit, finished with 22, including 16 in the second quarter. Riley, a UCLA signee, scored 14 of his 16 in the second half and made key rebounds and free throws in the final minute.
The loss dropped Oak Hill, last season’s DICK’S Sporting Good Nationals champion, to 13-1. It was the Warriors’ first loss since they fell to 22 Feet Academy of South Carolina on Nov. 14, 2015, a span of more than 50 games. The Warriors went 42-1 last season.
Thanks to 61 percent shooting in the first half, Sierra Canyon led 42-38 at halftime with Bagley and Martin combining for all but nine of their team’s points. The lead grew to seven at several junctures in the third quarter.
A pair of Riley baskets around a Matt Coleman lay-in gave Sierra Canyon a 73-70 lead with 2:46 remaining. Martin’s drive pushed the lead to five.
A pair of Coleman free throws with 58.3 second left cut the Sierra Canyon lead to 79-76.
Coming out of the timeout, Bagley was fouled on a spin move but missed both free throws. Billy Preston challenged Bagley at the rim on the other end and was fouled. He made one free throw to cut the lead to 79-77 with 34.5 remaining.
Riley was then fouled for Sierra Canyon and made one of two for an 80-77 lead with 31.2 seconds. Oak Hill had a pair of shots at the other end but eventually Riley pulled down the rebound and was fouled with 21.1 seconds left. He made both and Sierra Canyon had a five-point edge.
Coleman again made two free throws for Oak Hill, but the Warriors would not get closer than three in the final seconds.
Iowa State signee Lindell Wigginton finished with 21 for Oak Hill. Coleman had 13 points and Preston, a Kansas signee, had 13.