Isaiah Thomas and John Wall will be taking part in a matchup of top point guards in their Eastern Conference semifinal series. (Maddie Meyer/Getty Images)

BOSTON — As patrons at the Equinox gym in the middle of bustling Boston Common peered through glass walls to get a peek at NBA players conducting practice, the Washington Wizards tried to maintain their Zen. They open up their Eastern Conference semifinal series Sunday against the Boston Celtics, a team whose metaphorical funeral the Wizards once dressed for during the regular season. But on Saturday, having just endured a first-round series against the Atlanta Hawks full of talk of mixed martial arts and failed attempts to stay out of foul trouble, the party line was to downplay any potential bad blood between the two teams.

“It’s not a rivalry,” Wizards guard John Wall said. “This is the first time we’ve played them in the playoffs.”

“It’s basketball,” Wall’s backcourt mate Bradley Beal added. “We’re not fighting out here. We both play hard. We both are competitive. We both want to win … we’re going to keep it clean.”

The Wizards spent their entire time in front of reporters Saturday setting a tepid tone for the series, but there was one aspect of the Celtics no one on Washington’s team dared to diminish. Isaiah Thomas, Boston’s fiery, 5-foot-9 point guard who ended the regular season as the third-best scorer in the NBA, was not to be minimized.

“It’s always great to go against another great point guard,” Wall said. “I just went against another good one, a young player in Dennis Schroder that’s proving himself in this league and trying to get better. The first time ever having the keys to the team, he did a great job running that group.

“Now you got a different matchup in Isaiah, who’s the head of their snake, one of the best scorers in this league.”

Wall and Thomas make up one of the most compelling point guard matchups in these playoffs. Thomas averaged 28.9 points per game in the regular season, behind the league’s two leading MVP candidates in Russell Westbrook and James Harden. In Boston’s first-round matchup against the Chicago Bulls, he averaged 23 points per game on 43 percent shooting from the field. And Wall ascended to true superstar status this season, a level of prestige he reinforced Friday night, when he turned in a career-high 42 points — including 19 in the fourth quarter — as well as eight assists and four steals as he helped the Wizards eliminate the Hawks in six games.

Neither point guard is afraid to speak his mind. Both carry the expectations of cities with NBA franchises on the upswing. It’s a pairing that should be catnip to NBA fans.

“It’s definitely exciting,” Wizards backup point guard Brandon Jennings said. “John’s come into his own. I just feel like this series right here is going to put him to where people are going to want to pay attention to him and know who John Wall is. I think this is his opportunity right here to show the world. Because Thomas, you know, he’s like an MVP candidate. And John wants to be an MVP candidate, too. Isaiah averaged 30, he had a great year, their team is No. 1 in the East, so yeah. It’s an opportunity.”

But Washington Coach Scott Brooks can’t promise how much opportunity Wall will have to go one-on-one with Thomas, simply because the Celtics guard is too much for one defender to handle for an entire series. Kelly Oubre Jr. matched up against Thomas occasionally during the regular season, and both members of the Wizards’ backcourt will get his chance against Thomas this series.

“Well, we’re going to have to throw many different guys at Isaiah and many different schemes at him,” Brooks said. “You’re not going to get away with the daily guy, the same thing against one of the best players in basketball. The way he plays — he’s hard to stop. He’s fun to watch. He’s not fun to coach against, but he’s definitely [among those] MVP type of players.”

The Wizards, who had ups and downs defensively during the series against the Hawks, know they cannot afford Thomas any slack. The all-star point guard has a penchant for explosive fourth quarters in particular.

“He gave us fits a few times,” Brooks said. “He gave 29 teams in the league fits. He can get wherever he wants to on the floor, his ability to play pick and rolls, ability to score in transition … he gets to the free throw line. He’s a handful. We’re going to have to stop him — not one guy, our whole team’s going to have to do the best job that we can to stay in front of him and make him take tough shots.”

Washington couldn’t downplay Thomas’s talent Saturday, but Brooks, Wall and Beal all spoke about the point guard with a tone of respect that bordered on deference. Thomas’s younger sister was killed in a one-car accident the day before Boston opened its first-round playoff series against the Bulls, and Thomas was at home in Washington state Saturday to attend the funeral. Wall, who is friendly with Thomas, said he texted his counterpart after he heard the news.

“That’s a tough time he went through,” Wall said. “But … he was there because his teammates needed him, and he knew he could go out there and help those guys. Without having that great family and brothership that they have on their team, he probably wouldn’t have been able to get through what he got through.”

Note: Brooks said backup center Ian Mahinmi (left calf strain) is out for Sunday’s Game 1.