LSU (26-1, 13-0 in the Southeastern Conference) led just 37-31 at halftime, but went on a 24-2 run to start the second half as Arkansas missed its first 17 shots from the field.
"It was just strong talk at halftime by coach (Pokey) Chatman," Johnson said. "She was an All-America point guard (at LSU) and I'd rather pick things up myself before she starts fussing."
The 5-foot-3 Johnson's previous high was 24 points in a 78-62 LSU win over Tennessee for the SEC Tournament championship at North Little Rock in 2003.
But this was the third straight time she led LSU to 90 or more points against Arkansas in the past two seasons.
"I'm happy this little one is on my team," Chatman said. "The thing that separates her from any other point guard is she can score. That's nice to rely on when the shot clock is running down."
Johnson, a 67 percent free throw shooter, even made 12 of 12 free throws as LSU sank 23 of 25 from the line.
LSU All-America shooting guard Seimone Augustus scored 18 points and Scholanda Hoston added 16 for the Tigers, who shot 54.2 percent and outrebounded Arkansas 47-26.
"I was not pleased with our 21 turnovers, but I was happy with our offensive execution and board work," Chatman said.
Danielle Allen, despite a day-long touch of the flu, led Arkansas with 13 points. Kristin Peoples, Rochelle Vaughn and April Seggebruch added 12 points each, but Sarah Pfeifer scored just 6 points on 3-of-17 shooting.
Chatman said LSU tried to make Pfeifer work hard on defense, shoot difficult shots and not get second opportunities.
But Chatman admitted that during its 0-for-17 drought, "Arkansas got some wide-open looks that didn't fall."
The Lady Razorbacks (15-11, 3-10 SEC) led just once at 5-4 but whittled LSU's lead to 70-56 with 5 minutes, 40 seconds left before the Tigers finished the game on a 20-8 run.
Seggebruch, whose 12 points matched a season high, said Gardner had warned the Lady'Backs to keep up their intensity in the second half.
"She talked about LSU's runs all week," Seggebruch said. "But when you go 0-for-17, that's definitely a problem."
Sylvia Fowles, a 6-foot-5 freshman center, scored 11 points in just 15 minutes for LSU, sitting out much of each half after getting hit in the head early in the game.
"Sylvia got a little dizzy," Chatman said.
Still, Gardner credited Fowles' presence with affecting some of Pfeifer's inside shots.
With LSU sagging inside on Pfeifer, Arkansas made 10 of 23 from 3-point range, its most in SEC play this season. Peoples' 4 of 9 led the way.
The Lady'Backs were just the second SEC team and fourth team overall to score 60 or more points against LSU this season.
"If we play LSU again in the SEC Tournament, we've got to put two halves together," Gardner said.
A second-round matchup with LSU at Greenville, S.C., next week is a possibility, as Arkansas would likely nab the No. 9 seed by winning at Kentucky (14-13, 3-10) on Sunday.
Under that scenario, the Lady'Backs would meet the No. 8 seed at noon Thursday in the first game of the tournament, with the winner advancing to play LSU at noon Friday.
But an Arkansas loss at Kentucky would consign the Lady'Backs to the No. 11 seed and an 8:30 p.m. first-round game on Thursday against the No. 6 seed.
Johnson, LSU Sprint Past Arkansas 90-64
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