Jeff Teague had a simple answer to the question everybody was asking: “The ball slipped out of my hand.’’

Before the Celtics beat the Hawks, 104-95, in overtime Sunday night to send their first-round series back to Atlanta tied at two games, Boston had to survive regulation. Teague afforded the Celtics that opportunity by failing to get a good shot off on the final play of the fourth quarter.

The Hawks took back-to-back timeouts with 15 seconds left, the score tied at 92. The play they drew up — a chance to counter Celtics coach Brad Stevens’s call for an Isaiah Thomas driving layup the possession prior — gave Teague the ball at the top of the key and the clock ticking away.

Teague took a couple of steps to his left, but as he pulled up to shoot a 3-pointer the ball flew straight up. He had another chance, but in one motion — jump, catch, shoot — sent an airball well short of the basket.

Before the slip, the sequence unfolded as the Hawks had hoped: Drain the clock and give Teague the final shot.

“You want to exhaust the clock in that situation. You want to take the last shot,’’ Hawks coach Mike Budenholzer said. “Jeff just ended up like mishandling it a little.’’

The Hawks opted for Teague (who finished with 13 points on 4-for-18 shooting) over Paul Millsap (19 for 31, game-high 45 points). Millsap said afterward he had no problem with that.

Teague had hit 3-pointers on back-to-back possessions in the final minute. Millsap, who seemed to have a hard time while being guarded by Marcus Smart late in the game, had scored once in the previous five minutes.

“Jeff had the opportunity to take a guy [Thomas]. He had a good look. The ball slipped out of his hand,’’ Millsap said. “But the [plan] was for him to be aggressive and try to make a play for us. Down the stretch, he did a great job of keeping us in it, made some big shots down the stretch. So we trusted him to win the game for us.’’

Added Hawks forward Kent Bazemore: “The ball just slipped out of [Teague’s] hands. I’m not sure why or how. But we should have pulled it out in overtime.’’

The Hawks didn’t pull it out in overtime, however, rendering Millsap’s big night irrelevant. He added 13 rebounds, 4 blocks, and 3 assists after scoring a combined 26 points in the first three games of the series.

“Paul Millsap had a monster game, and his force and the way he played was great,’’ Budenholzer said. “I just think we needed a little bit more with him, collectively from all of us, a little more to help Paul tonight.’’

Millsap had 33 points — nearly double his average on the season — by midway through the third quarter.

Stevens switched Smart to Millsap midway through the fourth. Through the final 13 minutes — Stevens’s estimation of how long Smart guarded the Hawks’ 6-foot-8-inch, 246-pound forward — Millsap made only 2 of 6 shots. He missed both of his overtime attempts.

“I think what kind of got us out of whack was they put Marcus Smart on Paul, and we started trying to force it to him,’’ said Hawks guard Kyle Korver (10 points). “It kind of took us out of what we had been doing.’’

Millsap sounded less inclined to give Smart credit.

“Just guarded me at the right time,’’ Millsap said. “He’s tough. He is a tough guy. Forty-five minutes [of playing time], you know, no excuse. If I get the ball down there, especially having the night I had, I’ve got to make it work. So I blame myself for not being aggressive down the stretch and putting the ball in the hole.’’

Tim Healey can be reached at timothy.healey@globe.com. Follow him on Twitter @timbhealey.