INDIANAPOLIS — Although Kyrie Irving hit his customary array of acrobatic layups and jaw-dropping dribble drives, the shorthanded Celtics won Saturday night because of their depth.

For the second consecutive game, the combination of Terry Rozier and Marcus Smart dazzled. Still, the Celtics took until the second half before they concentrated and defended, rallying from a 13-point deficit to top the Pacers­, 108-98, at Bankers Life Fieldhouse.

Irving led the Celtics with 25 points on 11-for-20 shooting, and Smart added 15 points on 7-for-8 shooting. Smart started in place of Jaylen Brown and added 6 rebounds, 5 assists, and 2 steals. Rozier sparked the third-quarter run with some significant baskets on his way to 17 points.

Al Horford dominated in the paint with 21 points, 6 assists, 5 rebounds, and 3 blocks.

The Celtics were coming off a convincing win in Boston over the Orlando Magic on Friday night and won for the second consecutive time after their 16-game winning streak was snapped Wednesday.

Lance Stephenson scored 16 points for Indiana but just 2 in the second half, while Myles Turner led the Pacers with 19.

Boston was playing without Brown, who was in Atlanta to attend the funeral of his best friend, and Marcus Morris (rest).

Once again, the Celtics waited until the third quarter to become defensively engaged. They swarmed the Pacers with traps and double teams, forcing Indiana into one-on-one play late in the shot clock.

The Pacers looked somewhat comfortable in the first half attacking the rim and draining open 3-pointers. The Celtics outscored Indiana, 37-16, in the third period, holding the Pacers to 6-for-18 shooting and 0-for-6 from the 3-point line.

Most of the Celtics’ third-quarter run occurred with Irving on the bench. Rozier scored 8 points in the period and Horford, who was aggressive offensively from the tip, scored 12 points in the period, including a long 3-pointer to even the game at 66 with 4:05 left.

Boston ended the quarter on a 19-4 run in the final 5:04 and took an 82-70 lead into the fourth, again looking like a completely different team than the first half.

While the Celtics received a break when Indiana’s leading scorer, Victor Oladipo, was ruled out Saturday with a sore knee, they were presented with the mercurial Stephenson, who has a well-earned reputation of being wildly inconsistent but capable of dominating a game.

The Celtics saw the good Stephenson in the first half as he led Indiana with 14 points and played under control. He scored 12 points in the opening period as the Pacers shot 70.7 percent and led, 32-27.

And instead of trying to take over the game with questionable on-court decisions, he played distributor in the second period as Indiana, seventh in the league in scoring, gashed the Boston defense by repeatedly scoring at the rim.

The Pacers attacked the rim against the Celtics’ soft interior defense or drained 3-pointers. They were 6 for 12 from the 3-point line in the first two periods, including a pair from Stephenson.

Second-center Domantas Sabonis, acquired from Oklahoma City in the Paul George trade, added 11 points off the bench as the Celtics had no one to match his size in the post.

Meanwhile, the Celtics missed numerous open shots, including a combined 2 for 10 on 3-pointers from Irving, Jayson Tatum, and Semi Ojeleye.

With the team shorthanded, Celtics coach Brad Stevens had to dig deep into his bench.

Daniel Theis got the start over Aron Baynes and missed all three of his attempts at the rim in the first half.

Gary Washburn can be reached at gwashburn@globe.com. Follow him on Twitter @GwashburnGlobe.