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Celtics vs. 76ers preview: How to defend Philly's young stars, Boston's offensive questions, what to watch for

All-Star centers Joel Embiid and Al Horford will see plenty of one another over the next couple of weeks, with an Eastern Conference finals berth on the line. (AP)

No. 2 Boston Celtics (55-27) vs. No. 3 Philadelphia 76ers (52-30)

Let’s start here. Even if you love Al Horford — and there are a lot of reasons to love Al Horford — the Philadelphia 76ers employ two of the three best players available for their 2018 Eastern Conference semifinals series against the Boston Celtics, which begins Monday night at 8 p.m. ET.

Ben Simmons and Joel Embiid are the absolute truth, two ascendant stars capable of bossing a game in their own discrete and destructive ways. Simmons controls timing and tempo, pushing the pace at every turn to make scoring opportunities materialize out of thin air while seamlessly defending four positions with an alarming calm for a 21-year-old. Embiid represents finality, the possession’s logical endpoint for both his team and yours; get him the ball on the block and the odds are good that he’s scoring or getting fouled, and get it near him in the paint and chances are you’re either pulling it back out, getting it sent back in your face or watching it get yanked off the rim.

Yes, they are young, and yes, this is only their second postseason series. But they are elite talents, game-plan-wreckers and world-breakers. Boston just needed seven games to get past a Milwaukee Bucks team that only had one of those.

Philly’s got two, plus a perfect third man in gap-filling forward Dario Saric, an All-Defense-caliber wing in Robert Covington, and a trio of veteran shooters — J.J. Redick, Ersan Ilyasova and Marco Belinelli — who snipe and screen and cut relentlessly, giving space, shape and sting to the Sixers’ attack. This is a friggin’ squad, one that has won 20 of its last 21 games dating back to mid-March, and that seems to be hitting its stride at the absolute right time … even if it’s a little earlier than most observers expected.

Boston’s got talent, too, to be fair; Horford’s not surrounded by stiffs. Unfortunately, though, he’s also not surrounded by much scoring right now. Neither Kyrie Irving nor Gordon Hayward, the All-Star offensive focal points Danny Ainge imported last summer to build on the previous offseason’s addition of Horford, will suit up in Round 2. Jaylen Brown, the Celtics’ second-leading scorer in the win over Milwaukee, is doubtful for Game 1 with a hamstring strain, and while the early reports are that it’s of the more mild Grade 1 variety, those suckers can linger.

Terry Rozier (left) and rookie Jayson Tatum will have to pick up the offensive slack for the Celtics to challenge the 76ers’ defense. (Getty)

Much will depend on the Celtics’ complementary contributors — wunderkind wing Jayson Tatum, sixth-man scoring threat Marcus Morris, understudy-turned-mainstay Terry Rozier — finding ways to consistently convert scoring chances and cash in on them against a defense that finished the regular season ranked third in the NBA in points allowed per possession, and posted the East’s stingiest D in Round 1. The key to that, in all likelihood? Keeping Rozier, who roundly outplayed Eric Bledsoe last series to pick up Irving’s slack, from breaking down the defense off the bounce, forcing a shift or rotation that opens up Boston’s wings for catch-and-shoot opportunities.

If Brown can’t go, forcing a less dangerous wing scorer — say, chaos agent Marcus Smart — into the lineup, then Philly will be better positioned to deploy one of its top perimeter stoppers, Covington or Simmons, on the Celtics point guard while leaving the other to deal with Tatum. And if screwing with Rozier’s pick-and-roll game leads to either turnovers or missed shots, the 76ers could absolutely feast in transition, where they turned small cracks into double-digit advantages against Miami, and where Boston at times struggled to limit the Bucks in Games 3, 4 and 6.

Much will also depend on how Celtics coach Brad Stevens chooses to match up with Philly’s young bulls, and how effectively Simmons and Embiid can manage their respective matchups. Horford, a legitimate All-Defensive candidate who spent a lot of time on Giannis Antetokounmpo early in Round 1, spent significant time on both of the Sixers’ stars during the regular season, logging 68 possessions as Simmons’ primary defender over three games and 43 checking Embiid in two meetings, according to NBA.com’s matchup data.

The 76ers struggled to generate buckets in those matchups, scoring just under 90 points per 100 possessions when Horford checked Simmons and 86 points-per-100 when he defended Embiid — both would rank several sub-basements below the worst offensive efficiency marks of any team during the course of the full season. That’s the thing about having two of them, though: Horford can only take one. So where does Stevens turn to handle Door No. 2?

During the regular season, the most common answer was using bruising big man Aron Baynes, with whom Sixers coach Brett Brown is intimately familiar from their years together with the Australian national team, to bang bodies with Embiid, albeit with middling success; Philly generated 61 points in 52 Baynes-on-Embiid trips during the regular season, a monster number buoyed by the bigger and quicker Embiid’s ability to draw fouls. Matching up that way also likely allows Embiid to more frequently stay at home in the paint defensively rather than having to chase a legit 3-point threat like Horford out on the perimeter, opening up windows on the interior that Embiid, one of the league’s most threatening rim protectors, would otherwise slam shut.

The Celtics will have their hands full trying to defend 76ers rookie Ben Simmons, who nearly averaged a triple-double in Round 1. (Getty)

Stevens could elect to keep going small, then, as he did in the second half of the Bucks series when he made the surprise insertion of rookie forward Semi Ojeleye — 6-foot-7, 240 pounds, built like a supersized fire hydrant — into the starting lineup to guard Antetokounmpo. It wasn’t foolproof; Giannis did average 23-11-6 over the final three games of the series. But having the muscular Ojeleye shadowing and bodying him did slow Antetokounmpo down some, sap his assertiveness and efficiency, and help derail the Bucks’ most bankable source of offense. Ojeleye logged just 21 total minutes of floor time against the Sixers in three regular-season meetings, but might Stevens opt to try his hand with the same strategy against another nigh-on-impossible combination of size and skill without a threatening jumper?

But while Simmons isn’t as good overall as Giannis is at this point, he’s a more natural playmaker — preternatural, sometimes borderline supernatural — and the bet is he’ll figure out a change-of-pace like Ojeleye. During the regular season, the book on him was to hang back as far as possible to try to wall off his drives and take away his passing lanes, because you didn’t have to worry about him taking shouts outside the paint. He ate up that space at every opportunity, averaging 16 points, eight rebounds and eight assists per game while shooting 54.5 percent from the field. So Erik Spoelstra decided to crank up the Heat in Round 1, deploying multiple big, long, hard-nosed and gifted defenders — James Johnson, Justise Winslow, Josh Richardson — to get directly in the rookie’s grill and try to bully him at every opportunity … and Simmons averaged 18 points, 11 rebounds and nine assists per game while shooting 50 percent from the field.

Simmons isn’t indefensible; Horford had success limiting him during the regular season, as have others. But deploy your best defender to take him out of the game, and you’re likely giving Embiid — who shot just 41.7 percent from the field with 15 turnovers in his three-game opening round as he worked through rust and the discomfort of a new mask protecting his surgically repaired orbital bone — more opportunities to go off. Flip the arrangement, and you’re relying on some combination of Ojeleye, Morris and a potentially limited Brown to keep Simmons from wreaking havoc off the bounce. Plug one leak, another springs open, and before long — with Embiid battering on the block, Simmons putting pressure on the rim, Redick and Saric cutting into every open space, Belinelli and Ilyasova bombing away — the dam bursts.

(The wild card, as always: Smart, who gives up six inches and about 20 pounds to Simmons, but whose tenacity and knack for getting under dudes’ skin has made him Stevens’ in-case-of-emergency-break-glass option to disrupt an opponent’s go-to offensive weapon.)

The Celtics are disciplined, tough and elite defensively. They’ve got an excellent head coach and home-court advantage, both of which matter in the playoffs. They only count for so much, though, in the face of elite two-way talent at the vanguard of an advancing force. The Sixers can score enough to beat the Celtics four times in seven games, but without Kyrie or Hayward on the ball, I don’t think the same is true in reverse. Two years ago, the 76ers won 10 games. In two weeks, they’ll be playing in the Eastern Conference finals. Life comes at you fast. Ring the damn bell.

Prediction: 76ers in 6

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Dan Devine is a writer and editor for Yahoo Sports. Have a tip? Email him at devine@oath.com or follow him on Twitter!

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