LOS ANGELES (AFP) — Minnesota Timberwolves All-Star center Karl-Anthony Towns has a meniscus injury in his left knee and will miss "a significant period of time," ESPN reported on Thursday.

Citing unnamed sources, ESPN reported Towns is undergoing further evaluation to determine whether a surgical procedure is indicated or whether he could undergo rehabilitation that would see him return to National Basketball Association action more quickly.

The news comes with the Timberwolves tied with the Oklahoma City Thunder atop the Western Conference standings, both teams with 43-19 records.

Towns has averaged 22.1 points and 8.4 rebounds in 60 games this season, earning a fourth All-Star nod.

His offense has been a key contribution for a Timberwolves team that has relied on defense in leading the West for much of the season — ranking 18th in offensive efficiency.

The Timberwolves listed Towns as "out" for Thursday's game against the Pacers in Indianapolis with left knee soreness.

But they did not immediately provide further details on the injury to the Dominican-American.

Towns was sidelined from late November until late March last season with a right calf injury, playing in just 29 regular-season games.

He had missed just two games so far this season.

Meanwhile, Brooklyn guard Ben Simmons will miss the rest of the NBA regular season because of his ongoing back trouble.

The former top draft pick from Australia, a three-time NBA All-Star, missed the entire 2021-22 season with back issues before undergoing surgery for a herniated disc in May of 2022.

This season he has played just 15 games because of the injury.

"Ben Simmons will remain out for the remainder of the season while he consults with specialists and explores treatment options for the nerve impingement in his lower back," the Nets said in a statement.

"Simmons, along with his representatives and Nets medical personnel, are currently in discussions with numerous experts to determine the course of action that will provide him with the best opportunity for long-term sustainable health."

Simmons averaged 6.1 points, 7.9 rebounds and 5.7 assists for the Nets this season.