Lonnie Walker was the unlikely hero for the Los Angeles Lakers as they defeated the Golden State Warriors to leave the NBA champions on the brink of elimination from the play-offs.

Walker scored 15 points in the fourth quarter as the Lakers completed a dramatic 104-101 victory.

It puts them 3-1 up in the best-of-seven series.

The Miami Heat also moved 3-1 up in their series against the New York Knicks after a 109-101 win.

Jimmy Butler led the way with 27 points and 10 assists for Miami, who had five players in double digits, and the eighth seeds can clinch the series with a win on Thursday (00:30 BST) in New York.

The Golden State, with Stephen Curry to the fore yet again, were 84-77 ahead going into the fourth quarter of their match in LA.

But the introduction of 24-year-old Walker, who has struggled to establish himself since joining the Lakers on a one-year contract last year after battling a series of injuries, changed the game.

The Lakers went on to outscore their opponents 27-17 and Walker was mobbed by LeBron James and other Lakers team-mates on the buzzer.

James, who scored 27 points in the victory, said he had urged Walker before the game to be ready to help out.

“I’ve been telling him ‘Lonnie, you stay ready. We’re going to need you at some point’,” James said.

“For him to be as young as he is, to have that professionalism, to come out and stay ready when his number was called… We don’t win this game without Lonnie Walker tonight, that’s for sure.”

The Lakers will take a 3-1 series lead to San Francisco for game five on Thursday (03:00 BST) with the Warriors, who were led on Monday by Curry’s 31 points, 10 rebounds and 14 assists, needing a win to keep the series alive.

Meanwhile, the Denver Nuggets centre Nikola Jokic has avoided a suspension after Sunday’s incident involving the Phoenix Suns owner Mat Ishbia.

During the game, the ball went out of bounds and ended up in the hands of Ishbia, sitting in the front row. As Jokic tried to get the ball back, Ishbia held on to it and, after it came loose, the Serb pushed Ishbia with the outside of his forearm, sending the 43-year-old back into his seat.

Jokic was given an unsportsmanlike technical foul and has been fined $25,000 (£19,818) by the NBA “for making improper conduct with a spectator sitting courtside”.