LeBron James was repeatedly queried on JR Smith's blunder in Game 1 Thursday night which led to him abruptly leaving the postmatch press conference.

A monstrous performance from James saw him score a career-best postseason tally of 51 points, eight rebounds and eight assists as it looked like the Cavaliers would upset the odds and win Game 1 against the Golden State Warriors at the Oracle Arena.

Cavaliers guard George Hill was at the free throw line after he was fouled by Klay Thompson and had the chance to give his team the lead as they were trailing 107-106 with just 4.7 seconds left in the fourth quarter.

After burying the first free throw, Hill missed his second but as JR Smith got the rebound, instead of looking to score, dribbled out the clock as he thought they were ahead in the game.

By the time he realized it was still a tie game at 107-107, his pass to Hill was too late as the latter's shot was blocked and the game went into overtime with images later showing James incensed with Smith's moment of madness.

The Warriors had blown multiple leads in the second half but would not blow this golden opportunity presented to them as they ended the game in overtime, scoring the first nine points and eventually winning 124-114 to take a 1-0 series lead in the NBA Finals.

It comes as a huge disappointment for the Cavaliers as despite being one of the biggest underdogs in NBA Finals history, they had a chance to steal Game 1 and take advantage of a Warriors side playing without Andre Iguodala. James in the process, also became the first player to score 50 points in a Finals game and still lose.

"I just do whatever I can to help my team," James told reporters after the game when asked about his performance. "...I just tried to do that tonight."

When asked about Smith's blunder, James claimed he didn't know if the former knew the game was tied or not but maintained he would not give up on him, stating they have to "move on" despite a disappointing loss.

"We got to move on. This game is over and done with, we got opportunities," James explained. "I will never give up on JR, it's not in my MO, I never give up on my players."

There was also a controversial call in the fourth quarter as the Akron native had seemingly drawn an offensive foul from Kevin Durant with 36.4 seconds left only for the officials to overturn it and pin the foul on James with Cleveland head coach Tyronn Lue claiming his side were robbed because of it.

"I thought I read that play just as well as I read any other play in my career, defensively," James said. "I was outside the charge line, stepped in, took the contact. It's a huge play... I knew I took the hit, I don't know what else to say."

Despite the best effort of the Cavs, James did not take consolation from their performance though he did acknowledge this was their best performance of the postseason.

"I do not. I do not [take consolation]," James added. "We played as well we've played all postseason. We gave ourself a chance possession after possession."

The 33-year-old was then asked about Smith once again by a reporter and whether he knew what the latter's mindset was and if he knew the score.

"I thought we were all aware of what was going on [in terms of the score]. I didn't know what JR was thinking," he responded. "I don’t know his state of mind."

James was not sure what the reporter expected him to say who would then repeat his question of whether he knew if Smith knew the score before the former got up and left the press conference.

Game 2 will take place at the Oracle Arena again on Sunday.