Videos: What is driving the Boston Celtics' unexpected success?

I'll tell you what isn't driving the Boston Celtics in the postseason - hubris.

It's not Gordon Hayward, the big free agency signing of the summer, either.

It's not Kyrie Irving, the big trade target picked up in the offseason.

Nor is it Daniel Theis, the surprisingly effective German big man who brought a Marcus Smart-like intensity to the frontcourt.

This team has faced adversity almost from the opening tip of the season, and still found ways to win.

So what is driving Boston's unexpected success in the postseason, then?

Some people think it might be the coaching.

Others, the youth movement.

Or maybe just Jayson Tatum.

Still others, Al Horford's steadying veteran presence.

Or maybe Mook Morris' defense!

Some of them are even throwing Danny Ainge a bone for his skill in putting all these pieces together.

But with so much turbulence from last season to today, there's really only one thing that can explain it, something greater than the sum of its parts (coughcoughubuntucough).

All the above are part of the explanation of how the Celtics have overcome unfathomable challenges with seemingly inexplicable victories. To paraphrase regular reader Manny Loco, "18 in 18" isn't sounding so "loco" anymore.

For more stories by Justin, click here.

Image: Jesse D. Garrabrant/NBAE
Video: ESPN/TNT/SI/Boston Celtics
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