The bamboo sprouted on a sweltering September evening at the Rose Bowl, after so much waiting, so many doubts.

It was the realization of one of Chip Kelly’s favorite motivational mantras involving the giant timber bamboo. If you water the bamboo in the first year, nothing happens. If you water it in the second year, nothing happens. If you water it in the third year, nothing happens. If you water it in the fourth year, it grows 90 feet in six weeks.

In Kelly’s fourth year at UCLA, after a whole lot of nothing, the bamboo was visible throughout the Bruins’ 38-27 victory over No. 16 Louisiana State.

It was visible in the playmaking of tight end Greg Dulcich, whose fancy footwork led to one touchdown after he juked a defender and nearly another when he converted a crucial third down and was stopped just short of the end zone.

It was visible in a defense that continually stifled the Tigers, pressuring their quarterback and making them all but abandon a rushing attack that mostly ran in place.

It was visible in the coach who stuck with his one-day-at-a-time vision amid a mountain of losses and criticism, Kelly’s team having a really good Saturday after so many fall flops.

The Bruins (2-0) provided their beleaguered coach with a signature victory that could catapult them into the national rankings for the first time since 2017 while likely knocking out the Tigers (0-1).

“Overrated!” chants could be heard from the crowd of 68,123 over the final minutes.

Dulcich caught three passes for 117 yards and running back Zach Charbonnet showed he wasn’t a one-game wonder, running for 117 yards and a touchdown in 11 carries to top 100 yards for the second consecutive week.

The fourth quarter was one extended celebration after a new LED display flashed from light banks high above the stadium, UCLA players bopping on the sideline to Tupac Shakur’s “California Love.”

Fans held up lights inside the momentarily darkened stadium, the festive mood heightened by the Bruins’ 24-20 lead heading into the final 15 minutes.

Things would only get a lot more fun.

Dulcich helped extend the advantage when he took a pass from Dorian Thompson-Robinson on third and 14 and ran to the one-yard line as part of a 19-yard completion. Running back Brittain Brown scored on the next play, giving extending his team’s cushion to 31-20 with 12:28 left.

UCLA wide receiver Kyle Philips provided the exclamation point when he caught a pass and outmaneuvered two defenders near the sideline as part of a 45-yard touchdown that removed any remaining drama.

Not even a 45-yard touchdown pass from LSU quarterback Max Johnson to receiver Kayshon Boutte with four minutes left could diminish the fun.

The Bruins received an emotional assist from athletic director Martin Jarmond early in the fourth quarter when he took a microphone and told fans to “Get on your feet, stay on your feet the whole time, let’s go!”

Struggling to move the ball against UCLA’s defense, LSU got an unlikely assist midway through the third quarter. A referee stood between Bruins defensive back Jay Shaw and Boutte, screening Shaw as Boutte hauled in a short pass and ran for a 44-yard touchdown that pulled LSU to within 21-17.

The Rose Bowl was rocking early in the third quarter after UCLA quarterback Dorian Thompson-Robinson patiently waited for wide receiver Chase Cota to come open cutting across the field. The duo connected on for a 14-yard touchdown catch that Cota punctuated by leaping across the goal line as the Bruins surged into a 21-10 lead.

Thompson-Robinson exhibited the sort of poise that his LSU counterpart failed to display a few moments earlier. While facing heavy pressure, Johnson fired a pass directly to UCLA linebacker Caleb Johnson, who returned the interception 34 yards to the Tigers’ 17-yard line.

UCLA held a 14-10 halftime lead after slippery moves from Charbonnet and Dulcich offset some indecisiveness from Thompson-Robinson.

Charbonnet eluded three defenders on a 20-yard run early in the second quarter and converted a third down after catching a short pass and picking up a vicious block from Philips that went for a 35-yard gain.

Two plays later, all Charbonnet had to do was wait for a huge hole to open before he charged ahead for a 12-yard touchdown run that gave the Bruins a 14-7 advantage following their second consecutive score.

Dulcich had provided UCLA’s first touchdown after he cut across the field and took a short pass before appearing as if he might get tackled around LSU’s 37-yard line. That’s when he generated even bigger roars by sidestepping a defender and rambling ahead, finally tumbling into the end zone while being dragged down at the end of a 75-yard catch.

Everything about the game screamed big, from the eight NFL scouts in the press box to the two white-haired Orange Bowl representatives wearing faded sports coats that looked like they were from the Howard Schnellenberger era.

LSU displayed some swagger long before the opening kickoff when coach Ed Orgeron walked down a ramp leading into the stadium and, acknowledging a nearby UCLA fan, told him to “Bring your ass on, in your sissy blue shirt!”

The Tigers fans announced their arrival with boisterous “LSU!” chants when players took the field for warmups. But the game ended with fans in purple and gold streaming toward the exits, the Bruins having announced the arrival of a new day after a long-awaited breakthrough under Kelly.

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