Memphis Grizzlies guard Ja Morant, 23, is under scrutiny from the N.B.A. again after he flashed an object that looked like a gun in a carefree manner during an Instagram Live video posted over the weekend.

The Memphis Grizzlies said in a statement that they had suspended Morant from all team activities pending the league’s review. Mike Bass, a league spokesman, said the N.B.A. was “aware” of the post and was gathering more information.

This is the second time Morant has been disciplined for off-court conduct in the past three months.

In March, the league suspended Morant for eight games after he was seen holding a gun while dancing at a nightclub near Denver.

N.B.A. Commissioner Adam Silver noted Morant’s “enormous following and influence” in the announcement of that suspension, which classified the gun incident as conduct detrimental to the league. The Instagram Live video was posted early on March 4, when, the N.B.A. said, Morant had been “in an intoxicated state.” Morant soon left the team and checked into a facility in Florida for counseling.

“I’m going to take some time away to get help and work on learning better methods of dealing with stress and my overall well-being,” Morant said at the time in a statement, which was posted on Twitter by Tandem, the agency that represents him.

In contrast to Sunday, when the Grizzlies suspended Morant, the team responded to March’s incident less pointedly, simply saying that Morant would step away from the team. Grizzlies Coach Taylor Jenkins shied away from criticizing Morant when addressing reporters then and offered few details about any conversations he or the team might have had with Morant.

Morant later said going to counseling was his idea.

The nightclub incident was just one in a series of concerning off-court situations for Morant going back to last summer, some of which involved people who said they felt threatened by Morant or his associates, according to reports in The Washington Post and The Athletic.

After Morant returned from the March suspension, he showed a mixture of defiance and contrition. He said the journey that he began in counseling was a continuing process.

He was celebrated by Grizzlies fans during his first game back. Members of his family wore attire that said “redemption” on it. In comments after the game, Morant indicated that he felt unfairly targeted at times.

Still, that return was an opportunity for Morant to show that his stated desire to be better was sincere.

Morant is one of the league’s top guards. His signature shoe with Nike made its debut in March.

He just completed his fourth season with the Grizzlies, having come to the team as a small but electrifying point guard out of Murray State as the No. 2 overall pick in the 2019 draft. He is the leader on a talented young team that had been one of the best in the Western Conference all season even as Memphis coped with injuries to key players. The Grizzlies lost to the Los Angeles Lakers in the first round of the playoffs last month.

Last week, after Morant was not selected as one of the six guards on the three All-N.B.A. teams, he reposted a tweet from a Grizzlies beat writer that suggested that his off-court behavior might have contributed to his not being selected.