The assignment for Boston Celtics forward Marcus Morris in his first start this postseason was easy to explain but nearly impossible to execute.

His job: Guard LeBron James Authentic Rashaan Evans Jersey , and keep the four-time NBA MVP from running the Celtics out of their own gym in the Eastern Conference finals for the second year in a row.

”He’s obviously the best player in the game,” said Morris, who during the week boasted that he was up to the challenge and on Sunday explained why he wanted it.

”Because I’m a competitor. He’s the best player, and I’m going to be able to tell my kids this one day.”

Morris scored 21 points and added 10 rebounds while pestering James into a playoff-high seven turnovers – and a playoff-low 15 points – and the Celtics opened a 21-point, first-quarter lead to scorch Cleveland 108-83 in Game 1.

Jaylen Brown scored 23 points and Al Horford had 20 for Boston, which ran off 17 points in a row in the first and never allowed the Cavaliers within single digits again. The Celtics led by 28 when Cleveland coach Tyronn Lue pulled James for good with 7:09 left.

Game 2 is Tuesday night.

”I have zero level of concern at this stage,” said James, who was 5 for 16 from the floor and missed all five 3-point attempts.

”I’ve been down before in the postseason, but for me there’s never any level of concern – no matter how bad I played tonight, with seven turnovers, how inefficient I was shooting the ball,” he said. ”We have another opportunity to be better as a ball club coming in Tuesday night, and we’ll see what happens.”

Kevin Love had 17 points and eight rebounds, and James added nine assists and seven boards. The Cavaliers missed their first 14 3-point attempts of the game and shot just 32 percent in the first half.

By that time Luke Falk Jersey Titans , Boston led 61-35 – the biggest halftime playoff deficit in James’ career.

”I think we’re very alert to the fact that we’ll get a heavyweight punch on Tuesday night,” Celtics coach Brad Stevens said. ”It’s another great challenge, another great opportunity to experience something for this team.”

With injured stars Gordon Hayward and Kyrie Irving on the bench in street clothes, the Celtics continued their stunning run this season with what may have been the most surprising turn of events yet. A year after dropping the first two games at home against Cleveland in a five-game East final, the Celtics pounced on James, and the favored Cavaliers were never really in it.

”The last couple of playoffs, and our meeting at the end of year, they blew us out of the water,” Boston guard Marcus Smart said. ”We’ve got a different team, just like they do, and a lot of younger guys. So for them to see that, and have that feeling like we did tonight, is huge.”

TIP-INS

Cavaliers: Kyle Korver’s 3-pointer with nine minutes left in the third period was their first after missing 14 in a row. It cut the deficit from 28 points to 65-40. … Tristan Thompson had eight points and 11 rebounds.

Celtics: The Celtics improved to 8-0 at home this postseason. They do not have to win on the road to reach the NBA Finals. … Boston’s 36-18 lead at the end of one quarter was the second-largest in a playoff game in franchise history.

GET HYPED

The Celtics took the floor to a hype video that began with the broadcast of Hayward’s injury in the first quarter of the first game, at Cleveland. A variety of commentators predicted the team’s demise Will Dissly Color Rush Jersey , including Hall of Famer Charles Barkley saying: ”Their season’s over.”

As more players went down to injury – including Irving, who came over from the Cavaliers last summer but was done for the season in March – the prophesies grew even gloomier.

But there the Celtics were, back in the Eastern Conference finals against the Cavaliers for the second year in a row – with Hayward, Irving, Daniel Theis and Shane Larkin all injured and Stevens down to an eight-man rotation.

It was more than they needed.

Starting in place of Aron Baynes, Morris backed up his boast that he could cover James better than anyone except Kawhi Leonard. The Cavaliers star had seven of Cleveland’s nine turnovers after accruing eight in the entire four-game, second-round sweep of the Raptors.

”Our confidence level is very high,” said Morris, who recorded the first postseason double-double of his career. ”The younger guys to the older guys, we think we can compete and play with anybody. At the end of the day, all the talking is done off the court.”

FAST START

Horford made his first seven shots and scored 10, including eight straight, during the 17-0 run that turned a three-point deficit into a 21-7 lead. After James wiggled his way to a layup – Cleveland’s first points in 4 minutes, 43 seconds – Boston ran off eight more points in a row; Brown had six of them Cheap Will Hernandez Jersey , and he finished the quarter with 13 points and five rebounds.

Cleveland scored seven straight points early in the third and finished the quarter with six in a row to make it 78-64. But Boston made the first three baskets in the fourth and, after running off nine in a row to make it 96-68 with 7:09 left, the Cavs conceded.

UP NEXT

Game 2: Tuesday night, Boston.

The NFL Players Association filed a grievance with the league on Tuesday challenging its national anthem policy.

The union says that the new policy, which the league imposed without consultation with the NFLPA, is inconsistent with the collective bargaining agreement and infringes on players' rights. The filing met a statute of limitations deadline and will be heard by an independent arbitrator, an NFLPA spokesman said.

In May, the NFL approved its national anthem policy at its owners meetings in Atlanta. The policy allows players to protest during the national anthem by staying in the locker room, but forbids them from sitting or taking a knee if they're on the field or the sidelines.

Teams will be subject to fines if players don't comply and will have the option of punishing players.

When the league announced the policy, Commissioner Roger Goodell called it a compromise aimed at putting the focus back on football after a tumultuous year in which television ratings dipped nearly 10 percent; some blamed the protests for such a drop. The union said at that time that it would file a grievance against any change in the collective bargaining agreement.

The union said Tuesday it has proposed having its executive committee talking to the NFL instead of proceeding with litigation. The union said the NFL has agreed to those discussions.

The NFL declined to comment about the union's action.

In 2016, then-49ers quarterback, Colin Kaepernick began protesting police brutality and social injustice by kneeling during the national anthem, and the demonstration spread to other players and teams. It became one of the most controversial and sensitive issues in the NFL, with players saying their messages last year were being misconstrued Dante Pettis 49ers Jersey , while others 鈥?including President Donald Trump 鈥?called them unpatriotic. Trump even said NFL owners should fire any player who refused to stand during the anthem.

Following those comments, more than 200 players protested during the anthem that weekend before the number of protesters dwindled as the season progressed.

"We're here for a bigger platform," Raiders tight end Jared Cook said during the spring. "We're not just athletes. We're people that live this. It's people in our neighborhood, it's people that we grew up with, it's people that we know who are actually living through these circumstances. So when we speak on it, it's not like we're just speaking out of the side of our neck. It's things that actually touch home and things that we can actually relate to.

"All I have to say is, I just think it's sad that it's veered from something that stood for good and the whole narrative has changed into something that's negative when that was not what it was initially about in the first place."

The NFL started requiring players to be on the field for the anthem in 2009 鈥?the year it signed a marketing deal with the military.

"We want people to be respectful of the national anthem. We want people to stand," Goodell said at the May meetings, when he dismissed concerns about the lack of union involvement by contending the league met with countless players over the past year.

"We've been very sensitive on making sure that we give players choices," the commissioner added, "but we do believe that moment is an important moment and one that we are going to focus on."

The league and the Players Coalition have been working in tandem on efforts to support player initiatives in the community and for a variety of social issues. The NFL is committing $90 million over the next seven years to social justice causes in a three-segment plan that involves league players.

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