WASHINGTON — The White House was tinted green on Thursday, when President Joe Biden — secret service code name: Celtic — welcomed “Coach Joe” Mazzulla and the Boston Celtics to the South Lawn to celebrate the franchise’s unprecedented 18th NBA championship.

In a tradition believed to have begun when Bill Russell’s 1963 Celtics met with President John F. Kennedy, Biden welcomed the NBA’s 2024 champions and gave them a tour of the Oval Office. In all, the league’s most-decorated franchise has won at least one title in eight of the last 13 presidential administrations.

Celtics: More Than Just a Basketball Team

“The Celtics aren’t just a basketball team. They’re a way of life,” Biden told the crowd, quoting Celtics patriarch Red Auerbach before receiving a No. 46 jersey from All-Star Jayson Tatum and guard Derrick White.

Biden noted that his secret service code name is “Celtic.”

“For real. Because I’m Irish,” the president said. “Everybody behind me is Irish in their heart. I feel a special pride in this trophy. From this old Irish Celtic, to all you Celtics, congratulations.”

Biden, who was once one of the youngest senators in U.S. history and is now the country’s oldest president ever, said he felt a kinship with Mazzulla, who was 35 when he led the Celtics to the title in his second season.

A Celebration of Youth and Experience

“Joe’s the youngest head coach to win a title since the great Bill Russell,” Biden said. “I told him I used to be the youngest and now I’m the oldest. I liked being the youngest better.”

The Celtics were greeted with a band playing “Shipping up to Boston,” before Biden and team owner Wyc Grousbeck joined them on the risers facing the Washington Monument; green lights shined from from the eaves of the White House behind them. Among those in attendance were Massachusetts Gov. Maura Healey, Boston Mayor Michelle Wu and most of the state’s congressional delegation.

“I didn’t really know what to expect. I walked in, I was like ‘I’m more excited than I thought I was going be,” White told reporters afterward. “To be in the White House, to be where all the decisions — all the cool things — are happening, that was the best part.”

Celtics co-owner Steve Pagliuca said Biden’s 4-year-old grandson, Beau Jr., tried on his championship ring. (Oshae Brissett, a member of the 2024 team who is not with the Celtics this year, was at the ceremony and received his championship ring on Thursday.)

Biden also received a commemorative basketball, which he passed to Celtics center Al Horford. And then threw back and forth with a member of the crowd.

“I wasn’t expecting a pump fake,” White told reporters. “It’s harder to make a pass in a suit, so I was impressed.”

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Biden’s Knowledge of Celtics History Impresses

Biden was well-briefed on the Celtics history and their success last year, when they cruised to 64 wins in the regular season – their most since winning the 2008 title, and the fourth-best in franchise history. They went 16-3 in the playoffs, eliminating the Dallas Mavericks in five games.

Biden even noted that the ’24 Celtics had the highest ration of points per possession in NBA history – one of the wonkier stats, but one that had team vice president and stats guru Mike Zarren beaming.

“The basketball stats community has come a long way: the President of the United States is talking about points per possession!” Zarren posted on X after speaking to reporters at the ceremony.

Members of the Celtics organization went back into the White House after the festivities to meet with administration officials on pet issues, including “Raise the Age,” which seeks to have 18- to 20-year-olds treated as juveniles in the criminal justice system, and “Curbside Care,” which provides medical aid to new mothers in underserved communities.

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“This was a very exciting and moving day,” Grousbeck told reporters in a video call afterwards. “We had not been focused on this. We got through the banner and opening night, and then it was all business. Joe (Mazzulla) doesn’t want us to dwell too much on the past, he wants everyone to focus on moving forward. Having said that, everyone here, including Joe, seemed to have a great time.”

Zarren said he spoke to a secret service agent who was a Celtics fan and had to bear with the Golden State Warriors’ visit two years ago.

“He told them it was a bittersweet moment because he wished his Celtics were here. And they said to him, ‘Don’t worry, they’ll be here soon,'” Zarren said. “So for him, it was a good moment to see us show up inside there.”