Browns players send a message by standing during the national anthem. (Phelan M. Ebenhack / Associated Press)

With an assist from one of the greatest football players of all time, the Cleveland Browns continued to take a leadership role in sending a message about social justice during the playing of the national anthem Saturday night.

Last Monday, a dozen Browns players took a knee in prayer, with a white player joining in for the first time. Before the team’s game against Tampa Bay, nearly 30 players stood and joined hands for “The Star-Spangled Banner,” a group effort made at the suggestion of Hall of Fame running back Jim Brown, who met with players on Friday.

“Jim Brown’s message to us was, ‘Your message really becomes powerful when you’re unified,’ ” tight end Seth DeValve, the first white player to take a knee, said (via ESPN). “That’s what we’re trying to do right now.”

Brown was a leader when sports stars, such as Bill Russell, Kareem Abdul-Jabbar and Muhammad Ali, spoke out about civil rights in the 1960s and he was a participant in a historic sports summit to discuss the issues of the day.

“I’m going to give you the real deal: I’m an American,” Brown, 81, said on The Post Game last week. “I don’t desecrate my flag and my national anthem. I’m not gonna do anything against the flag and national anthem. I’m going to work within those situations, but this is my country, and I’ll work out the problems, but I’ll do it in an intelligent manner.”

Browns players said Brown had not told them what to do, merely emphasizing that they should act as a team after talking over the kind of protest that Colin Kaepernick first made last summer. That’s what the Seattle Seahawks did before the regular season opener last year and they, too, joined hands as they stood.

“We’re just trying to figure out the best way that we can go about our responsibilities and the things that we can do to try to impact the change,” cornerback Jason McCourty said after the game (via Cleveland.com). ” … We knew we wanted to change it up a little bit and we know we want to try to continue to get bigger numbers involved on our team of guys that are willing to do stuff and be a part of it.”

As the first Sunday of the regular season opener nears Sept. 10, there is a very real possibility that the protests will continue even though it won’t be widely seen because the national anthem is only televised before big games, like the Thursday night season-kickoff game and the Super Bowl.

“I just think numbers are an amazing thing,” McCourty said. “When we can get more guys — black, white, everybody just unified as a team — I think that will make the greatest impact.”

The Browns’ gesture comes after a week of intensifying discussion of the protest.

On Wednesday, about a dozen groups, including the Justice League NYC and Color of Change, marched in front of the NFL’s New York headquarters chanting “I’m with Kap.” The NAACP added its voice, sending a letter to Goodell and asking for a meeting to discuss why Kaepernick remains unsigned by any team. “No player should be victimized and discriminated against because of his exercise of free speech — to do so is in violation of his rights under the Constitution and the NFL’s own regulations,” wrote Derrick Johnson, the interim president and chief executive.

And baseball Hall of Famer Henry Aaron joined the chorus, telling Roland Martin that he thinks Kaepernick is “getting a raw deal.” Aaron added that he was bothered by the fact that “nobody has seemed to think that he stands a chance of being [a] number one [quarterback].”

Read more from The Post:

National anthem protests, and support for Colin Kaepernick, will add intensity to openers

A pro-Kaepernick crowd protests as NAACP requests a meeting with Roger Goodell

Sally Jenkins: Kaepernick blacklist risks hurting the NFL’s real priority: Its bottom line

‘We have work to do’: 12 Browns — including one white player — take a knee during anthem

Frank Serpico joins NYPD officers for rally in support of Kaepernick