Sam Hauser has been an underrated contributor throughout the NBA Finals

DALLAS — Sam Hauser’s box score numbers won’t jump out at you. But the 26-year-old sharpshooter — who has famously never shot below 40% from three in a single basketball season — has been critical en route to the Celtics taking a 3-0 NBA Finals lead.

His impact was the loudest in Game 3, when he helped the Celtics weather an early Mavericks’ storm by hitting 3 first-half triples — and finishing the night with 9 points (3-4 FG) and 3 rebounds. The Celtics fell behind by 13 points in their first quarter at the American Airlines Center, but Hauser’s poise to sink two threes in the opening period helped them crawl back into the game and ultimately regain control to take a commanding series lead.

Hauser hasn’t had an eye-popping offensive playoff run — nine points was the most he’s scored since the first round of the postseason against Miami, when he exploded for 17 points in the series-clinching Game 5. He shot just 7% from three (hitting 1 of 14 attempts) in the Eastern Conference Finals, dealing with uncharacteristic shooting woes that compelled him to rewatch his YouTube highlights in order to regain some confidence.

“Just to know I’m still the same guy — it’s just shots aren’t going in sometimes.”

But, even through those struggles, he continued to play double-digit minutes and served as one of the most reliable players off the bench, spacing the floor and helping open up lanes for teammates like Jaylen Brown, Jayson Tatum and Jrue Holiday to capitalize on.

“If they’re hugged on me in the corner, it creates a driving lane for someone else and creates an advantage that way,” Hauser said.

In the Finals, he’s been particularly effective, not just offensively but also doing all the little things, whether that’s getting stops on Luka Doncic or grabbing contested rebounds. He’s now shooting 5-11 from downtown in the series, fulfilling his role as best he can.

“Some shots went in, that was the only difference,” Hauser said of his Game 3 performance. “I thought I’d been playing pretty well throughout the series. Just trying to provide an energy spark.”

In Game 1, he was also instrumental in the early goings, scoring 8 points on 3-4 shooting, hitting both of his threes, and grabbing 4 rebounds. He managed to hold his own defensively, even when Doncic and Kyrie Irving hunted him on mismatches. And while he struggled with his shot in Game 2 (going 0-5 from three), the defensive intensity remained.

“He’s been able to stay level-headed through the ups and downs, and it’s been great to see,” Payton Pritchard said on Thursday. “He’s hit really big shots, and he hit three last night [in Game 3]. But, it’s just his work. He works on his shot all the time.”

Hauser said this morning that the chance to win an NBA championship was something he dreamed of as a kid.

“I feel like everybody in this profession probably does at some point or another,” he said. “We get to live it tonight.”

For the season, Hauser averaged 9 points and 3.5 rebounds in 22 minutes — all career-highs. He shot 42.4% from three on the season, second-highest on the team. Now, he’s hitting those shots on the biggest stage in basketball.

The enormity of that accomplishment — particularly for a player who went undrafted — is one he’s well-aware of.

“In the moment, you’re so locked in on the game that you’re not really thinking about it,” Hauser said.

But after Game 3, he took the opportunity to reflect on the significance of that accomplishment.

“You just kind of reflect on the game, like ‘whoa, I just a couple of shots in the NBA Finals. That’s pretty cool.’”