An incredible solo goal from Brahim Diaz secured Real Madrid a 1-0 win away at RB Leipzig in Tuesday's Champions League last 16 first leg.

Leipzig were energetic but wasteful early, while Madrid goalkeeper Andriy Lunin made numerous saves after the hosts controversially had a goal disallowed for offside.

The German club were made to pay early in the second half when Diaz opened the scoring.

Drafted into the side in place of the injured Jude Bellingham, Diaz danced past three Leipzig defenders before curling an inch-perfect shot inside the far post.

"I'm intuitive," said Diaz of the goal. "I saw Vini (Vinicius Junior) and wanted to give it to him, but in the end I took the shot.

"It was a nice goal."

Real midfielder Toni Kroos praised his teammate, telling Amazon Prime "a piece of individual skill decided the game.

"If we're honest, it could have gone in either direction."

The win was Real Madrid's seventh in seven games this Champions League campaign and puts them in prime position to make it past the last 16 for the fourth straight season.

"It was an open match," said Leipzig goalkeeper Peter Gulacsi, contending that "a lucky punch decided the game".

Madrid travelled to Saxony without England midfielder Bellingham, who injured his ankle in Saturday's 4-0 win over Girona.

With first-choice centre-backs Antonio Ruediger, David Alaba and Eder Militao ruled out, coach Carlo Ancelotti opted to continue midfielder Aurelien Tchouameni's stint in central defence.

Despite their injury woes, Real sit five clear in the league and have only lost twice this season in all competitions, both times to derby rivals Atletico Madrid.

Leipzig coach Marco Rose said Tuesday his side were "not afraid" of Real Madrid, having beaten the 14-time European champions 3-2 at the same venue in October 2022.

- Contentious decision -

The hosts thundered out of the blocks and had the ball in the net three minutes in, but the goal was ruled out for a contentious offside call, with Benjamin Henrichs deemed to be obstructing the goalkeeper.

Kroos said the wrong decision had been made.

"The goalkeeper would not have got to the ball, so it was a goal."

Gulacsi told reporters he was "frustrated" by the decision, explaining "1-0 after a couple of minutes could have changed the whole game."

Leipzig carved out a handful of half-chances but poor control in crucial moments, particularly from striker Benjamin Sesko, let the visitors off the hook.

Other than a trademark long-range effort from Toni Kroos which was gobbled up by Gulacsi, Real created little early.

Their best chance came late in the first half when Vinicius' looping cross drifted just above the head of an advancing Rodrygo.

Collecting the ball near the sideline just three minutes into the second half, Diaz was fouled but refused to go to ground, dribbling through the Leipzig defence before unleashing a curling shot past Gulacsi to score.

"We weren't able to dominate, but we played a good game," Diaz said.

"I'm happy to be able to help the side -- we continue to show we're a great team."

The goal cranked the home side into gear, with Barcelona youth product Dani Olmo going close to equalising, twice stinging the palms of Lunin.

Madrid should have had another with 20 minutes remaining after going on the counter, but Vinicius hit the post.

Lunin turned behind a searing strike from Sesko after Diaz went down injured, Leipzig's decision to play on enraging Madrid. The Ukrainian stopper also beat away a dipping effort from substitute Amadou Haidara.

Real host Leipzig in the Spanish capital on March 6.