BOSTON – Danny Ainge couldn’t have predicted this. Who could? Four years ago Ainge, the silver-haired Boston Celtics general manager, orchestrated the deconstruction of a fading contender. On Monday he was celebrating a trip to the Eastern Conference finals, while wishing his owner, Wyc Grousbeck, good luck in Tuesday’s draft lottery; Boston, owners of Brooklyn’s draft rights, has the best statistical chance of landing the top overall pick.

“Now that,” Grousbeck said, “is how you go to the lottery!”

Indeed. What a season. Boston is conference finals-bound, courtesy of a 115-105 win over the Washington Wizards on Monday, and on Tuesday will position itself to add another elite player to the mix. It’s like being handed a bag of cash, then having someone knock on your door the next day and hand you another.

Beating Washington wasn’t a surprise. The home team controlled this series. Of course it won in the end. Isaiah Thomas (29 points, 12 assists) was brilliant. Kelly Olynyk (26 points) was too. The Wizards expected problems from Thomas. They were ready for Al Horford. But a 48-5 battering from Boston’s bench? A 71 percent shooting night from Olynyk? When Washington tried to claw its way back into the game in the fourth quarter, Olynyk (14 points in the fourth) was there to beat it back.

Isaiah Thomas had 29 points and 12 assists in the Celtics’ Game 7 victory. (AP) More

As Thomas walked toward the interview room, he slapped hands with Celtics president Rich Gotham and pointed to Olynyk walking in front of him. “There he is,” Thomas said, smiling. “The new King of the Fourth.”

It’s Cleveland’s conference, but Boston’s message on Monday was unmistakable: We’re coming. The Thomas-Horford combination has been complemented by rapidly developing young talent. Marcus Smart didn’t make a shot in Game 6; he made four – including a pair of threes – in Game 7. Jaylen Brown, an afterthought in the first round, played nearly 20 minutes on Monday.

The Cavs have won eight straight to open the playoffs and will be heavy favorites. The Celtics? They expect it – and they are OK with it.

“We know it’s going to be tough, but at this point anything can happen,” Thomas said. “And we really believe it. They didn’t give us a chance in this series, they didn’t give us a chance when we were down 2-0 in Chicago. We got the No. 1 seed and they didn’t give us a chance. They don’t ever give us a chance, and we just keep going. We don’t care about what others say.”

Ainge is the architect of this stunning rebuild, but don’t expect him to croon about it. Success is fleeting, Ainge reminded a reporter, and this game has a way of humbling you. Ainge was a member of Boston’s 1986 championship team, which celebrated a title in June and the addition of Len Bias, the No. 2 pick, weeks later. Bias died shortly after the draft, a devastating loss no one saw coming.

The Brooklyn trade has already yielded one potential marquee player in Brown, and over the next two years could produce two more. Yet Ainge is loathe to revisit the deal, save to say that it pained him to do it.

“I don’t really think about that,” Ainge said. “When we made the trade, I was envious of [Nets GM] Billy King and [coach] Jason Kidd and where they were. With Paul [Pierce] and KG [Kevin Garnett], they were a contender. We were a team that was starting over. I was envious of where they were. It happens all the time, things change. This game humbles you. This job humbles you. We have had a very good year so far. Now we have a big challenge [in Cleveland].

“I don’t really think about [the assets]. Tomorrow we go right back to doing what we are doing. Maybe after the draft and free agency, maybe we will get excited about things. It’s like our players. They have 15 minutes to enjoy this thing, then they have to worry about playing Cleveland. That’s how I feel. The competition in the NBA is fierce. And the game humbles you.”

Story continues