Celtics X-Factors That Will Decide Boston's Fate Amid 2021 NBA Playoff Race

The Boston Celtics could win what's left of their 2020-21 NBA season and still fall short of expectations.

It's been that kind of year for the Shamrocks.

All could be forgiven, though, if the Celtics can recreate the playoff success they've enjoyed of late. If they booked their fourth Eastern Conference Finals trip in five years, few would remember the rocky regular season that preceded it.

That's still possible, by the way. With a dynamic wing tandem like Jayson Tatum and Jaylen Brown, Boston will always have at least a puncher's chance regardless of what it's up against.

But for the Celtics to deal a few knockout blows this postseason, they'll need the following three X-factors to rise to the occasion.

Evan Fournier

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The Celtics have been on the search for support scoring all season. At March 25's trade deadline, the hunt led them to Evan Fournier, who offered the promise of complementary points, passes and three-pointers at the bargain-rate price of two second-round picks.

The veteran swingman didn't have quite as much to give as his numbers suggested. If the Orlando Magic packed more of an offensive oomph, they wouldn't have leaned so heavily on Fournier, and he, in turn, wouldn't have netted 19.7 points, 3.7 assists and 2.8 triples per night.

In other words, the Celtics should've known they weren't getting a Gordon Hayward replacement. But they weren't paying Hayward prices either.

Boston doesn't need Fournier to punch above his weight class. Stabilizing the second unit and spacing for the stars is a good night's work. He just needs to do more of both consistently. There are flashes of what the Celtics hoped they were getting, but those must surface with more regularity in the second season.

Kemba Walker

Chris Carlson/Associated Press

Nagging knee issues hover over Kemba Walker like a storm crowd. It's too easy to worry that a wrong step here or a stumble there could either send the 6-footer to the injury report or sabotage his movement skills and therefore his efficiency.

Saying that, the C's have played it safe with him all season. He didn't hit the hardwood until the middle of January. It took him eight games to clear the 30-minute mark. He hasn't played both sides of a back-to-back set all season, and Boston has no plans of changing that.

"We have not even broached that topic," Celtics coach Brad Stevens said on 98.5 The Sports Hub's "Bertrand and Zolak Show," via Boston.com. "... Him feeling great has been a priority. It's a priority because we obviously value him. But it's also a priority because that's our best chance of peaking whenever the postseason begins."

There's a chance the Celtics are timing this just right. His field-goal percentage and assists average have climbed every month, and his first outing in May featured 32 points on 18 shots. If he can be the third wheel in a Big Three with Tatum and Brown, Boston could become a legitimate threat in the East just yet.

Robert Williams III

David Zalubowski/Associated Press

One can debate whether Robert Williams III is the Celtics' long-term answer at center, but this much seems certain: He's the most interesting player manning the middle since Al Horford skipped town.

Williams has long tantalized with length and bounce, both of which provide obvious perks on the glass and the receiving end of lobs. For as much as the modern game focuses on the three-ball, there's still a good amount of value in having an athletic rim-runner.

And Williams has a chance to be even more.

There's a wise-beyond-his-years thing happening with the 23-year-old's basketball IQ, and it surfaces just about every time he makes a pass. He may never be a point-center, but the Celtics have been hurting for complementary playmakers without Hayward, and Williams has been a pleasantly surprising contributor to the category.

But the difficulty level is only going up, as Boston could see the likes of Joel Embiid, Giannis Antetokounmpo and Bam Adebayo blocking its path out of the East. Williams is the best bet to battle those challenges. Whether he's up to the task will go a long way toward setting the Celtics' playoff ceiling.