Bill Plaschke (LA Times)  —  A home run. A half-court buzzer-beater. A game-winning Hail Mary. A hallelujah.

In the waning days of its worst football season in three decades, USC has pulled off the play of the year, defying all expectations, bucking conventional wisdom, making a miracle happen.

Did the Trojans really just hire Lincoln Riley? Pinch me.

Is their football team really going to be coached by arguably the brightest young football leader in the country? Revive me.

When USC fired embattled Clay Helton in the second week of September, Rick Caruso, the chairman of the USC board of trustees, promised to acquire “a world-class coach who will return the USC football program to the most competitive and highest levels of collegiate football.”

Promise kept.

In four of those five seasons, the Sooners finished in the top seven in the final Associated Press poll, while USC has not finished in the top seven in the final Associated Press poll even once in the last 10 years.

This is more than just the right coaching hire, this might be the most right coaching hire in USC football history.

“Today is all about the importance and impact of leadership,” said Caruso, who cited President Carol Folt as the driving force behind the move. “Dr. Folt changed the trajectory of this university and expects excellence at every level. She hired the best athletic director in the country in Mike Bohn. That set the stage to attract the best football coach in the country.”

Riley wins. Riley recruits. Riley entertains. Riley is perfect for that stage.

“Lincoln is the rarest combination of extraordinary person and elite football coach,” Bohn said in a news release. “His successes and offensive accolades as a head coach the past five years are astonishing. Lincoln will recruit relentlessly, develop his players on and off the field, and implement a strong culture in which the program will operate with the highest level of integrity and professionalism.”

An attribute that makes him perfect for Hollywood, Riley is best known for making magic with quarterbacks. While with the Sooners, he mentored both Baker Mayfield and Kyler Murray, back-to-back Heisman Trophy winners and No. 1 overall NFL draft picks. For an encore, he then mentored Jalen Hurts, a Heisman finalist, giving him three starting NFL quarterbacks in five years.

Think the latest Trojans quarterback prodigy, Jaxson Dart, is excited by this? Think maybe some those great Southern California prep quarterbacks who have been making a beeline to the powerhouse programs across the country will want to stay home now?

Riley, who grew up in the 5,000-person West Texas town of Muleshoe and later coached in Lubbock, Texas, and Greenville, N.C., before coming to Norman, Okla., is also used to being surrounded by the Midwestern toughness. It is something the prototypical West Coast Trojans lack. He will likely hire coordinators who will bring that fire. He will work with the offense to share that magic. He should fill a gaping void into which old-school Trojans football has completely disappeared.

“USC has an unparalleled football tradition with tremendous resources and facilities, and the administration has made a deep commitment to winning,” Riley said in the news release. “I look forward to honoring that successful tradition and building on it. The pieces are in place for us to build the program back to where it should be and the fans expect it to be. We will work hard to develop a physical football team that is dominant on both lines of scrimmage, and has a dynamic balanced offense and a stout aggressive defense.”

The Trojans haven’t won a national title in 17 years. They have only been in one Rose Bowl in the last 12 seasons. They recently allowed UCLA to score 62 points in the Bruins’ highest-scoring victory in the rivalry’s history. The Coliseum has never felt more empty. The future has never seemed so dire.

Enter Riley, who popped up on Bohn’s radar from the moment the plug was pulled on Helton after two games this season. This is Bohn’s first big hire since he was named athletic director two years ago. Caruso encouraged him to swing for the fences. Bohn had always admired Riley, even though he seemed untouchable.

When Oklahoma suddenly decided to leave the comfortable Big 12 Conference for the cutthroat Southeastern Conference this past summer, Riley was reportedly not thrilled with the decision and began feeling increasingly disconnected to the program. Bohn saw an opportunity, made some connections with Riley’s representatives and waited all season for the right moment.

That moment appeared Saturday night after Oklahoma’s loss to Oklahoma State ended the Sooners’ regular season with a 10-2 record. The college football world knew Riley was unhappy, and there were reports he was going to Louisiana State. In his postgame news conference, he denied those reports and expressed his love for the Oklahoma administration.

“We work well together, and we’ll continue to work well together,” he said.

Yet several hours later, in the early morning hours, he reached agreement with USC, which had Iowa State’s Matt Campbell waiting in the wings in case negotiations with Riley fell through.

Riley will rightly take some flak for misleading the media. He will also take flak for a 1-3 bowl record that includes going winless in his three College Football Playoff appearances with three awful defensive showings. In those big games, his teams lost 63-28 to LSU, 45-34 to Alabama and 54-48 in two overtimes to Georgia.

Riley has some things to prove. The sophisticated and demanding USC fans will be waiting, and not so patiently. He will initially enjoy a honeymoon, but if he loses to Fresno State in the middle of next September, that honeymoon will quickly end.

For now, anyway, it should be comfort enough that Riley could have gone many places, but he picked the Trojans, giving them their biggest win in many moons.

“The fact that he chose USC is a testament to the strength of our brand, the power of the Trojan Family and the leadership of our university,” Bohn said. “This is for our current players, our former players, our alumni, our fans, and our entire university community. Our time is now.”

Now, meaning Monday afternoon, when Riley shows up for his introductory news conference amid home runs, buzzer-beaters, Hail Marys and hallelujah.