In probably the most significant free-agent deal this offseason (outside of Stephen Curry and Kevin Durant returning to Golden State, which was a lock all along), Gordon Hayward agreed to sign with the Boston Celtics on Tuesday for four years, $128 million. It's hard to overstate how much this deal means to the Celtics, who have probably just vaulted themselves into at least fringe title contention

And probably even more important, they shot up our offseason power rankings!

Suffice to say, this offseason has been legit bonkers with all kinds of stars on the move and what appears to be a really exciting draft class. Based on all transactions to this point (with an honorable mention for the Sacramento Kings, who had an outstanding draft and followed it up by signing George Hill and Zach Randolph), here is a power ranking of the teams that have had the most successful summers. 

10. Toronto Raptors

  • Key additions/signings: Kyle Lowry, Serge Ibaka
  • Key losses: Patrick Patterson

The Raptors managed to re-sign their big-name guys in Kyle Lowry (three years, $100 million) and Serge Ibaka (three years, $65 million), but losing Patrick Patterson hurts more than the casual fan might realize. Check out this stat:

So the Raptors got a little worse, but so did the conference as a whole (although Hayward to Boston probably further separates the Celtics from the Raptors, so it's kind of a wash). In the end, re-signing star players is a win any way you cut it, and getting Lowry on a three-year deal rather than the full five-year max is a quiet win from a financial standpoint. 

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That's the reason the Raptors edge out the Kings. Starpower matters, and there's still some debate whether it was smart for the Kings to sign Hill, who will presumably take minutes from first-round pick and point guard of the future De'Aaron Fox. 

While Sacramento is still a long way from competing, Toronto is once again in play as the second-best team in the conference. If DeMarre Carroll and Jonas Valanciunas play closer to their contracts, it might be able to upset a team like Boston if things break right. 

9. Los Angeles Clippers

  • Key additions/signings: Blake Griffin, Danilo Gallinari
  • Key losses: Chris Paul, J.J. Redick

After losing Paul, there was almost no way the Clippers weren't going to get worse. The questions were: How much worse? Were they still going to be competitive or was a full rebuild going to be the play? The answers centered on Griffin, who was expected to meet with the Suns and Celtics, at least, as a free agent. Instead, almost as soon as free agency began, Griffin re-upped with the Clips on a five-year, $175 million deal. 

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The move leaves the Clippers with an All-Star-level duo in Griffin and DeAndre Jordan, and Tuesday they added Danilo Gallinari as part of a three-team trade. That's a darn good front court. 

It's still going to be tough sledding without Paul and Redick, who signed a one-year, $23 million deal with the Sixers, in a Western Conference that is even stronger with Paul George going to Oklahoma City and Jimmy Butler and Jeff Teague landing in Minnesota. 

But if you look at it like the Clippers' offseason kind of restarted after they lost Paul, then re-signing a star in Griffin, who definitely had a market elsewhere, and adding Gallinari is definitely enough to constitute a successful rebound. 

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8. Denver Nuggets

  • Key additions/signings: Paul Millsap
  • Key losses: Danilo Gallinari

Losing Gallinari sours the excitement of getting Millsap, who is arguably the highest-profile free agent the Nuggets have ever landed. Still, Denver finally hit a home run in Millsap and is quietly putting together a pretty nice team with Millsap next to budding star Nikola Jokic. Plus, Gary Harris, Emmanuel Mudiay and Jamal Murray still have a lot of upside on the perimeter. 

The unfortunate thing: Denver still plays in the West. The Nuggets added a borderline top-flight free agent and could still very well miss the playoffs. Also, Millsap, though a terrific player, isn't a guy who's going to carry a team, and $90 million over three years is a lot of money for a player who still needs a lot of help. 

7. Los Angeles Lakers

  • Key additions/signings: Lonzo Ball, Brook Lopez
  • Key loss: D'Angelo Russell

They got their guy in Ball with the No. 2 pick, but the real winning started when they shipped Russell and Timofey Mozgov's anchor of a contract to the Nets before the draft. Getting Mosgov off the books was huge. The Lakers have made some nice moves this summer and positioned themselves for a monster summer in 2018. 

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We all the know the deal: The Lakers are going to shoot for the moon next year when LeBron James, Russell Westbrook and George will be on the market. With presumed room for two max deals and George having already said he wants to play for the Lakers, there is obvious reason for optimism. The Lakers withstood the temptation to trade for George this year and are banking on getting him next summer without having to give up certain assets Indiana could have sought. 

On his own, Ball is a win. If he's what the Lakers think he is, they got their franchise point guard while clearing room to add two superstars next to him. 

6. Golden State Warriors

  • Key additions/signings: Stephen Curry, Kevin Durant, Andre Iguodala, Shaun Livingston, Nick Young, Omri Casspi
  • Key losses: None

Ian Clark, JaVale McGee and Zaza Pachulia are still unsigned, but if the decisions of Livingston and Iguodala, both of whom might have gotten more on the open market, are an indication, at least a couple of those guys will be back, too. 

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In essence, the Warriors will bring back the core of their title team, plus Nick Young -- who signed for one year, $5.2 million -- and Omri Casspi. Both those guys can shoot from deep and arguably make the Warriors' bench even stronger than it was last year. 

Curry, who was rightfully rewarded with the biggest contract in NBA history, was never going to leave, but Iguodala and Livingston were far from guarantees to be back. Keeping them is a big deal, and it can be largely attributed to Durant reportedly taking about $10 million less than he was eligible to make next season. Iguodala and Livingston keep the chemistry right. They keep the bench strong. One school of thought in closing the gap on Golden State was to chip away at its roster, taking some of the peripheral parts. That hasn't happened, and the Warriors again will be the heavy favorite to win it all. 

5. Philadelphia 76ers

  • Key additions: Markelle Fultz, J.J. Redick, Amir Johnson
  • Key losses: None

Trading up with Boston to get Fultz at No. 1 in the draft brings even more excitement to a franchise on a real upswing. A roster with Fultz, Ben Simmons, Joel Embiid, Dario Saric, Redick and Johnson looks like a legit playoff team in the East. In fact, our SportsLine projections have them as the No. 6 seed after inking Redick. 

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PHILADELPHIA 76ERS WINS WIN% PLAYOFF EAST SEED

Before Redick

39.7

48.4%

58.7%

8th

With Redick

42.0

51.2%

80%

6th

IMPACT

+2.3

+2.8%

+21.3%

+2

By signing Redick and Johnson to one-year deals, the Sixers seriously sped up the process, adding two veterans to mentor this young roster while continuing to keep their already flexible salary cap situation wide open. Philly is quickly becoming a place where legit free agents might well want to play. Someone owes Sam Hinkie an apology. 

4. Oklahoma City Thunder

  • Key additions/signings: Paul George, Patrick Patterson
  • Key losses: Victor Oladipo, Taj Gibson

The Thunder came out of left field to land George. As a bonus, they got rid of Oladipo's contract, which still has four years and $84 million left. People are still trying to figure out why the Pacers took this deal over other seemingly more attractive offers from the Celtics and Cavaliers, but they did, and OKC scored. 

Another score: Signing Patterson on a three-year, $16.4 million deal, which is an absolute bargain. He's not going to do much on the interior, but he really stretches the floor as a big shooter and plays good defense. Quietly, the Thunder are putting together a really good, versatile defensive team. If they bring back Andre Roberson, it gets even stronger. 

Why aren't the Thunder higher on this list? George could be a one-year rental, and Russell Westbrook has yet to sign an extension, meaning OKC still could lose both as free agents next summer. But let's not sour the mood by looking too far ahead. This is about this summer, and the Thunder just made themselves a potential top-three or even top-two seed if everything breaks right. 

Should the Thunder convince George and Westbrook to stay long-term, this will be one of the all-time great recoveries after Durant seemingly left the franchise high and dry last summer. 

3. Boston Celtics

  • Key additions/signings: Gordon Hayward, Jayson Tatum
  • Key loss: Amir Johnson

Gordon Hayward makes the Celtics a legit threat to the Cavs in the East and, perhaps, a fringe title contender, though that latter claim might still be a stretch. After Jimmy Butler, Paul George and Blake Griffin -- all guys who had been mentioned as possibilities in Boston -- wound up elsewhere, getting Hayward was crucial not just in terms of how much he helps now, but in also continuing to build toward what might be the brightest future in the NBA. 

Remember, next year Boston still has the Nets' first-round pick and a Lakers protected first-round pick, both of which could easily wind up in the top five. And let's not forget this year's No. 3 overall pick, Jayson Tatum, who hit a winner in his Summer League debut. He's an NBA-ready scorer with potentially elite skill for his size. And now, with Hayward on board, he won't need to play above his experience for the Celtics to take a real step forward. 

If Boston hadn't gotten Hayward, it would've been tough to call this summer anything other than somewhat disappointing at the least. Now it's a clear success. 

2. Minnesota Timberwolves

  • Key additions/signings: Jimmy Butler, Jeff Teague, Taj Gibson
  • Key losses: Ricky Rubio, Zach LaVine, Kris Dunn

Check out Minnesota's SportsLine season projections after adding Butler, Teague and Gibson:

OKLAHOMA CITY THUNDER WINS WIN% PLAYOFF WEST SEED

Without Butler, Teague, Gibson

38.1

46.5%

19.6%

12th

With Butler, Teague, Gibson (w/o Rubio)

46.0

56.1%

80.5%

6th

IMPACT

+7.9

+9.6%

+60.6%

+6

Look at those numbers -- from less than a 20 percent chance to make the playoffs to better than 80 percent. That, ladies and gentlemen, is what you call a huge summer. Making the situation even better is that Butler is under contract for two more years, so they have time to get this right. 

What a core that is developing in Minnesota, with Karl-Anthony Towns, Andrew Wiggins and Butler. Teague gives the Wolves more shooting and scoring than Rubio, and that's big because Butler and Wiggins aren't great 3-point shooters. Butler was almost certainly going to be moved from Chicago, and a lot of teams were interested -- notably Boston and Cleveland. Coming out with him is a big-time win for this franchise. 

1. Houston Rockets

Key additions/signings: Chris Paul, Nene, P.J. Tucker

Key losses: Patrick Beverley, Lou Williams, Sam Dekker, Montrezl Harrell  

How James Harden and Paul, two very ball-dominant players, will fit together is somewhat of a mystery, but from a pure talent standpoint, it's pretty hard to argue that the Rockets don't have the best back court in the league. Paul is a free agent next year, but by opting in on his contract with the Clippers before being dealt, he made it so Houston can give him the same max L.A. could've given him next summer. So this isn't necessarily the likely one-year rental situation OKC faces with George.

Putting Paul at the head of a Mike D'Antoni attack with this kind of shooting around him? Watch out. Ryan Anderson and Eric Gordon are going to be shooting practice jumpers. 

Beyond Paul, getting Nene to re-sign for $11 million over three years is a high-value deal, and Tucker is a hard-nosed player who you don't hear enough about. Both can really play, and Houston has a roster that could well be the second best in the West. 

Oh, and it was reported Sunday that Carmelo Anthony would be willing to waive his no-trade clause, with Houston being one of the teams on his radar. If that were to happen, Golden State might have a real threat to deal with in the Rockets.