For the boys basketball team from Phoenix Sunnyslope, it was as if someone had turned off the lights in the gym.

The Vikings struggled with their shooting, passing and defense in the first half of their game against Phoenix Thunderbird of the 2013 Arrowhead Desert Classic at Glendale Ironwood.

Then in the third quarter, someone flipped the switch back on.

Sunnyslope went on a 13-0 run to erase a 12-point deficit and went on to pull away in the fourth quarter for a 67-50 second-round victory.

Sunnyslope will play either Phoenix Brophy Prep or Buckeye in Wednesday’s (Nov. 27) next round. The winner of that game will advance to the championship game on Friday night (Nov. 29).

“A lot of it starts for us with our defensive intensity,’’ said Sunnyslope coach Ray Portela. “We came out flat, but in the third quarter we started moving into their passing lanes, pressuring them more, feeding off our own energy.’’

The Vikings will need to be more consistent as the season moves along. They were the No. 1 seed in last year’s Division II state tournament and fell to rival Phoenix Paradise Valley in the semifinals (PV would go on to win it all). Now they have moved to Division I.

They will rely on the play of 6-foot-9 senior Michael Humphrey, who recently signed with Stanford. He scored just six points in the first half but came alive in the second to score 16 more to finish with 22. He had a couple of thunderous dunks, one after his steal and one on an inbounds lob from the baseline.

“When you’ve got a weapon like that, you have to use him,’’ Portela said of Humphrey, who was the quarterback for Sunnyslope’s football team that went unbeaten during the regular season.

Junior Sammy Barnes-Thompkins also had a strong effort, scoring 15 points in the first half and eight more in the second, including a pair of 3-pointers.

The Vikings were without senior point guard Navareio Holmes, who was out because of disciplinary reasons. Portela said he could return on Friday if the team advances to the finals.

Thunderbird showed cohesiveness in the first half, but unraveled in the second.

Jake Glatting, who quarterbacked the Chiefs in football, led the team with 20 points, including four 3-pointers.