ATHENS, Ga. -- Coach Joni Taylor told Georgia's guards to pound the ball inside to Caliya Robinson and Mackenzie Engram all afternoon.
Taylor knew the Lady Bulldogs had too much size for Mercer to contain.
"We knew that was our advantage and we did a great job of making sure that we did that," Taylor said.
Robinson had 23 points and 16 rebounds, Engram added 21 points and 10 rebounds, and Georgia held off Mercer 68-63 in the first round of the women's NCAA Tournament on Saturday.
Que Morrison finished with 10 points and nine rebounds for the fourth-seeded Lady Bulldogs (26-6), who advanced to face Duke on Monday night.
Kahlia Lawrence scored 23 points and KeKe Calloway had 15 for No. 13 seed Mercer (30-3). The Bears had won a school-record 27 straight, the nation's third-longest active streak.
Georgia had the game's biggest lead at 11 early in the third, but let Mercer pull within one twice in the fourth quarter. After Robinson scored her team's last field goal with 2:14 remaining, the Lady Bulldogs put Mercer away by hitting seven of their last eight foul shots.
"They were out for blood, and I think they played awesome," Engram said. "But we pulled it out and kept our composure."
Mercer used scrappy perimeter defense, forcing steals and challenging passing lanes on every possession in which Georgia ran a set offense, but the Bears couldn't make up for a lack of size, getting outscored 32-8 in the paint.
"We decided to play to put more pressure on the passers, but we didn't do a great job with it," Bears coach Susie Gardner said. "Engram and Robinson are big-time players. We have Amanda Thompson at 5-9 getting nine offensive rebounds. How in the world? That's just heart."
Robinson hit eight of her first nine shots and had 14 points early in the second quarter. Georgia never trailed after Morrison assisted on her layup made it 30-28.
There were 11 lead changes and seven ties in the first half. The Lady Bulldogs took a five-point lead, the biggest lead before intermission, on Morrison's tip-in with 1:07 left in the second.
Morrison put back her missed shot on the first possession of the third and then followed with four free throws to make it 43-32, Georgia's first double-digit lead.
Calloway had nine points on 3 for 6 shooting before getting hurt at the 4:50 mark of the second quarter. She returned less than 2 minutes later and didn't take another shot until her 3 late in the third cut the lead to five.
Lawrence, a three-time Southern Conference player of the year, took several ill-advised wild shots late in the game and finished just 8 for 28 from the field, but she took advantage of a poor foul by Stephanie Paul at the end of the period.
Pulling up to take a long 3 before the buzzer, Lawrence was knocked in the arm with 0.4 seconds to go and sank three free throws to make it a four-point game entering the fourth.
"They obviously have two great post players that rebound the ball very well, but it wasn't just them that hurt us," Lawrence said. "Their guards got some very critical offensive rebounds and that did hurt us. We didn't stop fighting. We just fell short."
Mercer: The Bears enjoyed the best season in school history, tying Chattanooga's 2003-04 Southern Conference record for overall wins. Mercer moved into the Associated Press poll late last month, its first ranking since 1980. Lawrence, a senior, leaves as one of the Bears' career-best players. Calloway's 3 late in the third set a single-season conference mark for treys. She finished with 99.
Georgia: The Lady Bulldogs, winners in five of six, showed why they led the Southeastern Conference in field-goal percentage defense, holding Mercer to 31.8 percent. That's the formula that helped Georgia finish in a tie for second place during the SEC regular season, and the Lady Bulldogs will need a similar effort against Duke. Georgia went 16-15 last year and already has enjoyed the second-best turnaround in school history.
Georgia is 0-3 against Duke with their last meeting in the 2005 NCAAs. The Lady Bulldogs seek their 21st trip to the Sweet 16 and first since 2013.