This piece was updated after publication with new details concerning the trade between Boston and Philadelphia.

Celtics president of basketball operations Danny Ainge earned the nickname “Trader Danny” in Boston for making big deals that go against the grain. But Celtics fans may start calling him “Traitor Danny” after he traded the no. 1 pick in this year’s NBA draft. In May, the franchise won the draft lottery for the first time in its history. Following the heartbreak of missing out on Tim Duncan in 1997, Kevin Durant in 2007, Joel Embiid in 2014, and Ben Simmons in 2016, fans were excited. Now, the top pick is going to Philadelphia in a deal expected to be finalized on Monday, with the Celtics acquiring the 2017 no. 3 and a protected 2018 Lakers first, which will only convey if it lands no. 2 through no. 5. Otherwise, the Celtics will receive the more favorable of the Kings’ or Sixers’ 2019 first-round pick, unless the pick is no. 1, then the less favorable pick will be conveyed.

I wrote last week about how this could be the trade-down draft, and this deal gets that trend rolling. The first pick is rarely traded, so it makes sense that Celtics fans would be shocked — though the C’s have traded the one before (Joe Barry Carroll for Kevin McHale and Robert Parish). Ainge is also on the record as being an admirer of the 1993 Chris Webber–for–Anfernee Hardaway–and-future-firsts swap executed by the Magic and Warriors.

According to a high-level front-office source, the reason the Sixers “only” paid a price of two first-round picks is because both teams see little separation between no. 1 and no. 3. It’s more about preference of player — Philly loves Markelle Fultz’s talent and his fit with its developing roster. The timing of the deal and the protections on the pick suggests both teams were negotiating on common grounds. Of course, a lot can happen between now and the beginning of free agency. The Celtics could use the assets they got from Philly to acquire a star player like Paul George or Jimmy Butler; they could trade down again; or they could increase their cap space to push for max free agents like Gordon Hayward and Blake Griffin (if they opt out of their contracts). They have an overflowing treasure chest of picks and useful players like forward Jae Crowder and guard Marcus Smart they can package together if they want to.

Don’t be surprised if Ainge makes more moves this week. Two front-office sources I’ve spoken to said the Celtics have already explored the possibility of moving down again in the draft. As of now, there’s nothing on the table, but Boston is open to the possibility if the deal is right. The Kings are “starved” for Kansas forward Josh Jackson, according to The Vertical’s Chris Mannix. The vibe I get from chatting with league sources is there’s a distinct possibility that the Kings would look to move up ahead of Phoenix (no. 4) for Jackson, possibly using the no. 5 and no. 10 picks, but they’d need more back than just the no. 3 pick. If I were the Kings, I’d want Crowder, who is locked into a cheap deal through 2020, or Smart, who the Kings were targeting in the 2014 draft. It’s doubtful the Celtics would be willing to cough up either player, but they need to trim salary to have maximum cap space. The Kings have good reason to ask for a nice player in return.

I’ve been banging the trade-down drum like Keith Moon for the past few months because of the nature of this year’s deep lottery class and the particular needs of teams that lost out on lottery night. This is a trade that makes sense for both parties. I think Fultz is a special prospect, but he’s not a no-brainer generational talent, like Anthony Davis or Karl-Anthony Towns. The Celtics were right to add value by moving down and positioning themselves to acquire a prospect they rate similarly to Fultz — such as Duke forward Jayson Tatum or Kansas forward Jackson. The Sixers were also smart to move up. As covered Sunday, Fultz is an ideal fit next to Ben Simmons.

The way I’ve graded the prospects in this year’s draft, my top three rated players (Fultz, Tatum, and Lonzo Ball) on The Ringer’s 2017 NBA Draft Guide land in Tier 1. The next seven are in Tier 2. The difference between both tiers is not huge. This draft is unusually loaded with top prospects who would arguably go no. 1 in a “normal year,” so it’s hard to look at historical numbers as valuable. It’s true that from 1980 to 2012, the no. 1 pick yielded a multi-time All-Star 69.7 percent of the time, compared to just 45.5 percent at no. 3, and 27.3 percent at no. 5, per the Draft Express pick-expectations tool. But the numbers should be thrown out when independently evaluating the 2017 draft class, which has a big chunk of talent up top, then a steady drop-off. Not all years have a downward logarithmic slope. One NBA talent evaluator I chatted with months ago compared this year’s crop of lottery prospects to the 1999 class, which had five multiple-time All-Stars and four longtime starters in the top 10, then fell off quickly. Value charts should be adjusted accordingly based on future projections through the scope of historical precedent, but not solely on historical precedent.

Well, damn. That’s nearly 1,000 words on Boston’s draft-pick situation, and we haven’t mentioned the fact that the team just went to the Eastern Conference finals, and is the biggest prospective buyer of NBA star talent. By moving down in the draft, the Celtics not only add a future pick, they save about $1.4 million in cap space, and every bit will help in the tough act of reaching roughly $30.3 million needed for a run at Hayward or Griffin. There’s always the trade route, too.

“There could be more shoes to drop if this deal goes through,” the Boston Herald’s Steve Bulpett wrote on Friday. “And the Celts at least will be in position to offer a fair bundle of picks and younger players of value to a team that may be nearing the wall with a present star.” Adding the protected 2018 Lakers first, Boston has more ammo to make a push at one of the two superstars on the market.

Bulls forward Butler and Pacers wing George are two names that have come up in Celtics trade rumors in the past. Anthony Davis could also be a target, since players like him historically don’t stick around on teams like New Orleans, but that’s nothing but a dream for Boston right now. The Bulls and Celtics have talked about a Butler trade on and off since at least last year’s draft. Butler is a ferocious go-to scorer, gets to the rim at will, and plays hard-nosed defense. Conventional wisdom suggests Butler is the prime target. But George actually makes more sense. On Sunday, it was reported that George had informed the Pacers he planned to opt out of his deal at the end of next season, and The Vertical’s Adrian Wojnarowski reported that the Pacers have been “more aggressive in pursuing trades” for George. The problem for Indiana is that it has lost its leverage. It’s been reported for a while that George has a strong preference to join the Lakers. So teams other than the purple and gold will have to view George as a one-year rental. With a diminished market, George would be a cheaper acquisition than Butler, who is still under contract until 2019. The Bulls can be patient if they’d like to be. The Pacers are up against the clock.

We’re in Carmelo Anthony–Nuggets-Knicks territory with George. A star player has hit a ceiling with his team and reportedly wants out with a specific destination in mind. The Pacers can try to create a bidding war for George, but everyone knows where he wants to play, and he can just sign with the Lakers as a free agent next summer. The Pacers are “ideally” asking for two firsts and one starter, per David Aldridge. The Celtics could easily put that offer on the table. Other teams could, too, but that’s a lot to give for a rental.

This could theoretically backfire on Los Angeles. Let’s assume for a moment that Indiana manages to find an acceptable deal — whether it’s with Boston or someone else. Would the Lakers feel compelled to hop back in for a bidding war? I fail to see how the Lakers can feel confident George would still want to come to Los Angeles if he spends a season on a contender. They don’t need to give anything, but they could lose a lot by sitting on their hands. The Pacers have no leverage now, but with the right deal on the table, they could certainly create some between now and judgment day. The Celtics would be wise to be part of that PG13 party.

Some fans think Ainge created a dynasty for the Sixers by trading them the no. 1 pick, Fultz. Maybe that’ll end up being the case. But where the Sixers are decidedly building to be a competitor years down the line, the Celtics are trying to have their cake and eat it too. Ainge is trying to maintain optionality, with a blend of veterans and incoming draft picks, that’ll enable them to build for now and later. LeBron James is the gatekeeper of Eastern Conference for now. But in a post–Prime LeBron world, the Celtics and Sixers could be battling annually for the Eastern Conference crown.

It’s rare for a no. 1 pick to be traded. It’s even more unusual for a blockbuster trade to be a relative win-win for both sides. Sixers fans should feel ecstatic, and Celtics fans … take a breath, and count to 10. Are you feeling better now? OK, good. Your team just went to the Eastern Conference finals, has the no. 3 pick, can create max cap space, and has enough assets to trade for a superstar and still have some left in the cupboard. Trust the progress.