There is no such thing as a must-win NBA game in March -- but if the Los Angeles Lakers are going to reach their championship goals this season, they are going to have to start beating the LA Clippers.

It's why Sunday's centerpiece game at Staples Center (3:30 p.m. ET on ABC) -- officially a Clippers home game, but the Lakers have had few true road games anywhere -- is one of the more compelling left on the regular-season schedule. The cotenants play again April 9 in a rescheduled game, but it's the third night of a rare back-to-back-to-back for the Lakers, so don't count on that being representative.

With that in mind, it's important to note that the Clippers have been compiling victories of one kind or another against the Lakers since July. The list includes: Kawhi Leonard choosing the Clippers in free agency; a 112-102 win on opening night without Paul George, as Leonard scored 30 points and outplayed both LeBron James and Anthony Davis; and the Clippers collecting a 111-106 win on Christmas when George did play. Leonard scored 35 points on that outing, again outplaying James and Davis.

At the February trade deadline, the Clippers acquired Marcus Morris when both L.A. teams presented offers to the New York Knicks. That was quickly followed by Reggie Jackson securing a buyout from the Detroit Pistons. Both L.A. teams were again in competition for Jackson's services, and the Clippers were again the winners.

These victories don't earn the Clippers anything on the actual scoreboard on Sunday. They don't carry over to a potential hallway playoff series in May.

"One win doesn't mean an L.A. championship," Leonard said on Christmas. "Both teams got their eyes on the biggest prize."

But to say it doesn't matter isn't accurate either.

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For example, there is a story that has gained some notoriety in league circles. Late in the evening on July 5, when Clippers lead agitator Patrick Beverley learned at Las Vegas Summer League that his team had landed Leonard and George, he went to a private dining room where James was eating. To gloat.

"It's pretty much over for you guys now," Beverley said to James, retelling the story on The Woj Pod last month. "I had fun with it. And I really meant it from the bottom of my heart."

Leonard and George don't do that type of trash talking, but there is no mistaking the edge developing. It grew a little more salty when the Clippers overcame a 15-point Lakers lead on Christmas to take the latest meeting, punctuated by Beverley's late-game steal when he stripped the ball from James and secured the win.

There have been far more intense rivalries in James' long career -- he has said that they're developed in the playoffs. And the Clippers and Lakers have never met in the postseason. As a member of the Miami Heat, James played Leonard and the San Antonio Spurs twice in the Finals, splitting the outcomes. He played and beat George's Indiana Pacers three times. These days, James has had more intense standoffs with members of his own roster -- namely Rajon Rondo with the Boston Celtics and Dwight Howard with the Orlando Magic.

There's a healthy respect for the Clippers' stars, but not much vinegar.

So while this is more of a projected rivalry than an actual one, spend time in the locker room of either team and there's no mistake in the desire to win these games. Christmas Day had a huge buildup. And the tightness and intensity displayed in the game told the tale. Both rosters are stocked with veterans who know there's a strong chance the West's NBA Finals representative will be decided by this matchup.

Or, as James said: "This is what it's going to come down to, I think, at the end of the day."

From the Lakers' viewpoint, on opening night, James and Davis were still working on their chemistry. It showed as James looked to force-feed Davis in the post and it stalled out the offense. Then, on Christmas, James was bothered by a sore groin, and it might have limited his ability to drive. He wasn't his usual attacking self and was unable to deliver relief baskets as the Clippers roared back.

In neither game have the Lakers' two stars showed their best, combining to shoot just 39%. With the assumption that Leonard and George would play close to 40 minutes a game in a potential playoff series, the Lakers need to win the two-star race. Especially because the Clippers have the highest-scoring bench in the NBA and outscore opponents' reserves by an average of 18 points per game.

"We know we stack up against the best in the league no matter who it is -- win, lose or draw," James said. "It's going to be good competition."

From the Clippers' viewpoint, they barely have had a complete roster healthy throughout the season. Their current group at full strength is 10-0 and building major momentum with Beverley and George recovering from midseason injury issues. They will bring a six-game winning streak into Sunday, fresh off a blowout win over the Rockets in Houston on Thursday.

They've also tried possible playoff strategies on the Lakers and found some success -- including playing Leonard at power forward. They're 2-0 and don't think they've given the Lakers their best shot yet.

Perhaps that comes Sunday.

This is all a tale the Lakers will need to reverse. Perhaps they are poised to do so with James in the midst of his best play of the season: He is shooting 56.8% and has boosted his scoring average by four points per game since the All-Star break, as the Lakers have won seven of eight games during that span.

The next few years in the NBA might be defined by who controls Los Angeles, and this promises to be the most interesting chapter yet.