EARLY IN THE first quarter of Game 1 of the NBA Finals, the heavily favored Los Angeles Lakers appeared lethargic, disjointed. Coach Frank Vogel called time, down 23-10, and made some substitutions.

One of them, 34-year-old Rajon Rondo, who shot 41.8% in the regular season, surveyed the floor, noted the Miami Heat's defenders sagging off him to double Anthony Davis and promptly pulled up for an open jumper that -- naturally -- dropped through.

The next time down, with his dribble alive, always alive, the ball a cunning appendage of his massive hand, Rondo whipped a pass to Kentavious Caldwell-Pope for a corner 3. Swish. Timeout Miami. It was the start of a 75-30 Lakers run from which the Heat would not recover.

Playoff Rondo had struck again.

"I had heard about it, but in 2018, against Portland, that's when I knew he was different," says L.A. teammate Davis, who alongside Rondo with the New Orleans Pelicans eliminated the Trail Blazers from the playoffs that year. "He kind of reminds me of Bron [LeBron James]. Mentally, he locks in. He watches three to four previous games and breaks down their schemes: their offense, what this guy likes to do, what they like to run, when they like to run it, who they are running it for."

The origin of Playoff Rondo traces back to a young, unbridled, stubborn talent aiming to be a Celtics lifer. He was easy to overlook on the star-studded Boston roster -- until the postseason, when he unveiled a clutch shot, a key assist or a gutsy charge that would tip the scales. Former Celtics teammate Leon Powe says he remembers hearing "Playoff Rondo" for the first time in 2010, when Powe was playing with the Cleveland Cavaliers against Boston in the Eastern Conference semifinals.

"I'm pretty sure Perk started it," Powe says, "'cause when Rondo was destroying us, Perk kept shouting, 'Playoff Rondo!'"

"Might have been me," muses Kendrick Perkins, who remains one of Rondo's closest confidants. "I did call him that a lot, because he has a history of turning it on for the playoffs.

"His mindset reminds me of [former Lakers guard] Derek Fisher, who would go from scoring eight, nine points a night in the regular season, then all of a sudden pop off for 16 in a big playoff game."

Rondo has averaged 9.1 assists per game in the playoffs during his career. Among players to play 50 postseason games, only Magic Johnson (12.3) and John Stockton (10.1) have averaged more, per ESPN Stats & Information research. And according to Second Spectrum data, Rondo is shooting 46% on jumpers this postseason, up from 34% during the regular season. In fact, his numbers swell in every statistical category once the playoffs begin.

Rondo disdains his postseason alter ego because it discounts all the work he put in so he could perform in those critical moments -- the countless hours he watched film, created game plans for his coaching staff, shared his knowledge with any young player who responded to him on the team flight when he pulled out his iPad and offered to show them how to get better. Why does he hit big playoff shots? Because he scours the opponent for clues ahead of time, studying how they guarded players with skill sets like his.

The player who Alvin Gentry anoints the most intelligent he has ever coached is on the precipice of securing his second championship ring. Only Clyde Lovellette has won one with both the Lakers and the Celtics, the NBA's two most storied franchises.

"It's all about opportunity and belief from the coach," Rondo tells ESPN in a phone conversation conducted on the eve of Game 1 of the 2020 Finals. "If you give me minutes, let me manipulate the ball, let me be me, then my numbers will spike, and so will the team's.

"But the trust has to be there. And, obviously, that hasn't always been the case."

RONDO WAS ONCE an irritated Celtics rookie sharing time with Sebastian Telfair and angling for a trade. Coach Doc Rivers flatly refused, telling him, "You'll get where you want to go here."

By the time Rivers entrusted him with the ball, Rondo had memorized every play Boston had -- in addition to every play the opponent ran. Powe once asked him how he was able to remember them all. "I just need to glance at them two or three times," Rondo replied.

Rondo devoured film and emerged with ideas. Lots of ideas. Sometimes, they would jibe with his coach; and sometimes, they didn't. It made for a volatile relationship with Rivers, who would alternately push to send Rondo packing or grant him a lucrative extension.

"Rondo wanted to call a play he thought would work, but Doc would want to call something else," Powe says. "We're running up and down the floor and the two of them are arguing. Doc's shouting, 'Run what I drew up!' and Rondo is shouting back, 'I'll run your play but it's not gonna work!'"

Powe pushed back on the Cavs' scouting report in 2010, which stated the player guarding Rondo should feel free to leave and double because Rondo wasn't a perimeter threat.

"I tried to tell them," Powe says.

"Next thing you know, he's torturing Mo Williams, knocking down jumpers, draining 3s. I said, 'This is Playoff Rondo. He's different than regular-season Rondo.'"

In a double-overtime loss to the Atlanta Hawks in January 2013, Rondo, who had already been picked for his fourth All-Star Game, unknowingly tore his ACL on a seemingly innocuous play. He played on it for another 12 minutes and didn't receive the devastating diagnosis until two days later, navigating the injury the way he handled most everything else -- silently, stoically, internally.

"Before I tore my ACL, I was a different player," Rondo admits. "Afterwards, I was hesitant. The play that I hurt myself on was a little jump pass that I'd done a thousand times, but then, just like that, I had to learn to walk again.

"It tore me up mentally. I really had to think whether I wanted to play again."

When he finally returned to Boston after 12 months of grueling rehab, the roster was unrecognizable. Kevin Garnett and Paul Pierce were gone, replaced by Jared Sullinger, Brandon Bass and Kelly Olynyk. Rivers too had left for greener pastures with the LA Clippers, replaced by NBA newbie Brad Stevens.

Rivers had grown tired of Rondo believing he was the smartest guy in the room. And Rondo was weary of having his input questioned, even ignored. Their relationship has since come back around, and they both regularly engage in a group text with Garnett, Pierce, Perkins and Tony Allen.

"I only played for Brad for a while," Rondo says, "but I will never forget him spending the time getting to know me as a person, instead of coming in jaded because I was perceived as someone who wasn't coachable.

"You know why people say that? Because if you didn't know your s---, I'm going to call you on it."

IN DECEMBER 2014, the rebuilding Celtics dealt Rondo to Dallas, where superb tactician and no-nonsense coach Rick Carlisle awaited. The Mavericks were a team mostly devoid of shooters, a hole that Rondo could not fill. He challenged everyone, as he always did, but his ball-dominant style didn't mesh with the Dallas veterans. A dust-up with Carlisle over imploring Rondo to speed up play, while he pointedly walked the ball up, garnered headlines. Rondo was such a distraction that the Mavs took the extraordinary step of banishing him during their first-round playoff series, sending him away under the guise of a phantom back injury.

"It wasn't a good fit," Carlisle explains. "We were a far worse fit for him than he was for us. But I have great respect for Rondo. He's one of the best competitors of all time."

In 2015, Rondo moved on to Sacramento on a one-year, $9.25 million deal. The Kings were mired in a public power struggle between big man DeMarcus Cousins and coach George Karl, and Rondo vowed to be the buffer. Instead, the Kings lost 49 games, Karl was fired, Cousins was traded and Rondo was out of work again.

"After that, only one or two teams were calling, and I said, 'I've seen this story before,'" Rondo says. "Ever since Dallas, guys were trying to get me out of league. So many players get blackballed because of their supposed attitude. All of a sudden, nobody wanted to touch me."

BEFORE THE 2016-17 season, Rondo's longtime agent, Bill Duffy, was worried. "We had nothing," he admits. Duffy finally convinced Chicago Bulls general manager John Paxson to speak with famed Bulls international scout Ivica Dukan. Dukan's son, Duje, had played in Sacramento with Rondo the previous season, and Duje had raved about Rondo's impact on the young Kings players, so the Bulls gave Rondo a one-year audition.

For 21-year-old Bobby Portis, it was a career-changing moment. Rondo took him to dinner, patiently answered all of his questions and pored over game film with him. When Jimmy Butler and Dwyane Wade publicly torched the team's young players after a loss, Rondo charged to their defense, questioning Butler and Wade's leadership in an Instagram post.

"It was really cool for him take up for us," Portis says. "Every locker room needs someone who isn't scared of confrontation."

Portis says the Bulls would engage in shooting competitions after practice for money. Rondo, who might have had a poor shooting game the night before, would "suddenly hit 8-for-8, 9-for-9. He goes to a different level when there's something on the line that's meaningful."

When the Bulls drew Boston in the opening round of the 2017 playoffs, Rondo's relentless pursuit of the ball left a young Celtics team on its heels. Chicago won the first two games of the series on the road, but Rondo fractured his thumb and was done. Chicago folded in six games.

"If Rondo doesn't break his thumb," says Portis, "we win that series."

RONDO SIGNED WITH New Orleans in 2017-18, his fifth team in four seasons. Veteran Jameer Nelson, who spent the first half of that year on the Pelicans, marveled at Rondo's preparation, growing accustomed to receiving texts at 2 or 3 a.m. with stream-of-consciousness basketball ideas.

"Rondo will challenge everyone -- coaches, teammates, the front office," Nelson says. "But never once was it, 'We need to do X, Y and Z to make me look better.' It was about getting the best out of the team."

That included a young Davis, who despite his abundance of talent had only been to the playoffs once. Rondo made it clear he needed to do more.

"He was a huge help coaxing AD into the next gear," Gentry says. "He'd say, 'Man, you're better than this. We need more. You have to play to a level where you help us win games.'"

It was Davis, Rondo and backcourt mate Jrue Holiday who gleefully orchestrated a first-round upset over the Trail Blazers in the 2018 playoffs, with Rondo averaging a career playoff-high 12.2 assists and shooting 42.1% from the 3-point line.

"It was literally crazy," Gentry says. "When the playoffs start, Rondo is a completely different person. I think it's because he's playing the same team four, five, six, seven different times, so adjustments are important and tendencies matter. There's where Rondo always has the advantage -- when the game is cerebral."

The Lakers cited Rondo's IQ when they signed him, then quickly learned his willingness to challenge the best was an unexpected bonus. Amid a frustrating 2018-19 season, Rondo noted James souring on the young players and immediately confronted him.

"When guys are making the same mistakes over and over and over, it's hard to bite your tongue," Rondo says, "but I tried to get [James] to focus on his body language.

"Those young guys were looking at everything he did. If they missed four shots in a row and LeBron was making a face, it was crushing to them. He was their Michael Jordan. They didn't want to let him down. But if LeBron said one thing positive to Brandon Ingram or Kyle Kuzma, they immediately were back to their old selves."

Rondo's 2019-20 regular season with L.A. was underwhelming. The only season he averaged fewer assists (5.0) was in his rookie year, and yet another fractured thumb forced him to leave the NBA bubble to undergo surgery. He returned in mid-August, and the Lakers put together a string of wins.

"I honestly believe his return to the bubble saved the Lakers' season," Perkins says. "They were struggling without him. He takes pressure off LeBron and AD, and he turns the key in the back of role players like Caldwell-Pope and Kuzma, because he'll put them in the best position to succeed."

The return of Rondo enabled Vogel to rest James, knowing there was still someone on the floor to help Davis hunt easy baskets. The Lakers' offense has not missed a beat when Rondo is on the floor without James this postseason, rating 120.2 in offensive efficiency.

Rondo, L.A.'s veteran leader, figures he can play four more seasons before looking for a coaching or front-office job, which means it's now Vogel and Lakers general manager Rob Pelinka who field his late-night texts.

"I'm grateful for the opportunity," Rondo says. "I want to be the best role player there is. I don't need acknowledgement from other people on whether they consider me a winner or a great teammate."

The proof, Powe says, is on the court: The higher the stakes, the better the results.

"When you back up and dare him to shoot, he takes that as a form of disrespect," Powe says. "But he'll only shoot it if it's the right decision. If he thinks it's better to dive behind, go to the basket and get a flash dunk, he'll do that. If he thinks it's better to pass it to you, he will.

"Whatever he does, it will be the correct play. Because that's who Playoff Rondo really is."

ESPN's Dave McMenamin contributed to this story.

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