Cavaliers star LeBron James is still confident about his side's chances in the NBA playoffs despite a shock Game 1 defeat to the Indiana Pacers on Sunday at the Quicken Loans Arena in Cleveland, Ohio.

James finished the game with 24 points, 12 assists and 10 rebounds but was not able to prevent his side from going behind in the series as the Pacers won 98-80 after a blistering 33-14 lead after the first quarter, with guard Victor Oladipo scoring 32 points for the visitors.

Despite his triple-double, James shot just seven-for-17 and produced three turnovers in an overall team display that was met with boos from the home crowd.

The defeat also means the 33-year-old now lost a first round game for the first time since 2012 when the New York Knicks beat the Miami Heat. He was entering the contest with a 21-game unbeaten run and the best winning percentage in the first round at .872.

LeBron James LeBron James lost a first round playoff game for the first time since 2012. Pictured: LeBron James #23 of the Cleveland Cavaliers looks on during the second half while playing the Indiana Pacers in Game One of the Eastern Conference Quarterfinals during the 2018 NBA Playoffs at Quicken Loans Arena in Cleveland, Ohio, April 15, 2018. Pacers won the game 98-80 to take a 1-0 series lead. Photo: Gregory Shamus/Getty Images

Regardless, James is not worried as he and the Cavs have come back from worse predicaments, notably being 3-1 down to the Golden State Warriors in the 2016 NBA Finals, only to claw their way back and remarkably win the series 4-3.

"I've always stayed even-keeled with the postseason," James said after the game, as per ESPN. "I mean, I'm down 0-1 in the first round. I was down 3-1 in the Finals. So, I'm the last guy to ask about how you're going to feel the next couple days."

The likes of Jordan Clarkson (2-for-6 in shooting), Rodney Hood (3-for-7), Jose Calderon (0-3), and Jeff Green (0-7) were all off with their shots but the three-time NBA champion believes they will perform better as they continue to gain playoff experience.

"We had some guys in their first time out there playing in this setting and they definitely ... Like I told you guys, you always ask me, 'Is there anything you can tell them [about the playoffs]?' Listen, experience is the best teacher and they got it today," James added. "I think everybody is going to be a lot more calm and a lot more precise in what we want to do, too. So, it's definitely a feel-out game. We'll see what they're going to do."

In addition, James believes the intensity of a playoff game compared to a regular season game is what caused the Cavaliers to lose the first game of the series.

"I think the intensity. How much different a regular season game is compared to a postseason game. It happens that fast," he explained. "You always hear people say in the regular season, sometimes it's a 'playoff-type atmosphere.' Eh, you can't simulate that. You can't simulate that speed. You can't simulate what's going on out there."

"So, today was definitely a good test for some of our younger guys and like I said, I think they'll be a lot better, especially in Game 2. And not just them. Even the older guys as well. Some of the guys even with experience, including myself, I can be a lot better as well. So, we take it as everybody has to dig deep and not lose two of them on our home floor," James said.

Game 2 takes place at the Quicken Loans Arena on Wednesday as James and company look to peg the series back to 1-1.