BOSTON -- Boston Celtics guard Marcus Smart was struggling through what would become the NBA's worst shooting month in more than five decades. But with 0.9 seconds remaining in the first half of a late-season game against the Milwaukee Bucks, Smart could be seen imploring teammate Jae Crowder to inbound him the ball.

Crowder flipped the ball in Smart's direction and -- unfazed by the fact that 6-foot-11 Giannis Antetokounmpo was standing in front of him to further increase the degree of difficulty -- Smart launched a one-armed, 83-foot Hail Mary that hit only a security guard emerging from underneath the Boston basket as the buzzer sounded.

Watch any NBA game and a sequence like this plays out at the end of most quarters. But players hoping to preserve their shooting percentages often wait until just after the horn before unleashing their heave.

Not Smart. He's never met a 75-foot prayer that he didn't think he could make.

It's part of what makes Smart so endearing. Even as his shooting struggles are so routinely invoked by those who evaluate his game, the third-year guard makes no effort to stop launching the sort of shots that quietly chip away at his anemic percentages.

"I don’t think he’s as concerned about people blasting him as he is about winning," said Celtics coach Brad Stevens. "It gives you a chance to win if you make one of those. He doesn’t put much into stats, other than whether you win or lose. And I think that’s one of the things that you really appreciate about him."

As the top-seeded Celtics prepare to embark on their postseason voyage with Sunday's Game 1 against the eighth-seeded Chicago Bulls, it's well documented what Isaiah Thomas means to Boston's playoff success. But Smart might be Boston's ultimate X factor, the player whose performance is most likely to have an impact just how far this team advances in the postseason.

Yes, Smart's shooting percentages are an eyesore. For the month of March, he connected on just 45 of 157 field goal attempts (28.7 percent), which was the lowest percentage by an NBA player with 150 or more attempts in a calendar month since Chicago's Horace Walker shot 27.3 percent (44 of 161) in December 1961, according to Elias Sports Bureau.

And yet Smart never got gun-shy about his heaves. According to NBA's shot-tracking data, Smart launched 18 shots of 30 feet or longer this season and didn't make a single one. Half of those came from behind the midcourt stripe.

What's more, Smart took a whopping 95 shots with four seconds or fewer on the shot clock this season. Some of those certainly weren't rushed attempts, but at least 31 came with the shot clock turned off at the end of a quarter and others were the product of no other teammate being willing to rush up a late attempt.

"If you think about how many half-court or late-shot clock heaves I take, and you deduct that from what I actually shoot, then you would understand that has a lot to do with [his shooting struggles]," Smart said. "But it's OK."

For the sake of Smart's argument, we eliminated the 186 shots the NBA deemed to occur "late" in the shot clock (7 seconds remaining or less) this season. In all earlier instances, Smart connected on 213 of 547 attempts, or 38.9 percent. While it's still not much to write home about, it would help pull Smart from the basement of the shooting stats.

Among the 221 players with at least 400 field goal attempts this season, Smart ranked 220th at 35.9 percent overall, just hundredths of a percentage point ahead of Brandon Jennings.

It's fair to wonder if much of Smart's shooting woes could be remedied if he was simply more selective with his 3-point attempts. Smart shot just 28.3 percent beyond the arc, including a cringeworthy 25.5 percent on 247 attempts above the break. Smart was one of just 75 players in the league with at least 300 3-point attempts and the next worst percentage was Philadelphia rookie Dario Saric at 31.1 percent.

And yet it was impossible not to watch Smart consistently draining 3s while working with assistant coach Jay Larranaga after Friday's practice and wonder why it simply hasn't translated to games. With Larranaga positioned behind Smart and holding his back up, Smart made 3-point shots from every spot on the floor during a rigorous post-workout shooting session.

Smart downplayed the workout noting, "We do it every day. I come, get my shots up, and just really focus on shooting through the contact." But it's clear both the Celtics and Smart recognize that he could be even more of a force on the court, especially as the primary second-unit playmaker, if defenses had to respect his shot more.

Until that jumper becomes more consistent, Smart is content to have an impact in the game in every other way possible.

Earlier this week, Smart penned a piece for the Players' Tribune that recapped Boston's season and expressed hopes for a long playoff run. In it, Smart detailed one of his favorite plays of his career: Going to the floor with Kevin Garnett and earning a love tap from his veteran opponent for making a key hustle play.

Wrote Smart: "A loose ball. The sweetest sight there ever was."

This is quintessential Smart, who also memorably dove on the floor to snatch a loose ball from an opponent trying to walk the dog and save time on the game clock last season.

One Celtics fan made a mesmerizing 3-minute YouTube mashup of Smart simply wrestling the ball away from opponents throughout his career. It's not just that Smart is registering the steal, but how and when he makes these plays at key spots in games.

In Boston's first-round series against the Bulls, Smart will likely be tasked with defending Chicago's veterans at three positions, which means turns on the likes of Rajon Rondo, Dwyane Wade and Jimmy Butler. If Boston needs some help slowing a big man, Stevens might just call on Smart like he did last year when Atlanta's Paul Millsap caught fire in the playoffs (Smart's efforts helped Boston emerge with one of two victories in the series).

Teammates gush about Smart and the way he impacts winning. The hashtag #winningplays -- a reference to something Smart does in a key late-game spot -- will almost certainly trend at some point this month.

Along the way, Smart will probably miss a bunch of shots, too. Stevens doesn't care. He's repeatedly stressed how Smart could go scoreless most nights and he'd probably impact winning as much as anybody on Boston's roster.

Smart will just keep shooting, especially those long-distance heaves.

"You miss it -- especially full court, half court -- you miss, you not really supposed to make it," Smart said. "So if you miss it, it’s like, ‘Oh well.’ But if you make it, that’s a big momentum swing going into the next quarter or half."