A pair of LSU newcomers and one former Tiger made the biggest impacts in a sloppy game that featured 43 combined turnovers.
Former LSU player Louis Earl led all scorers with 17 points for HSG, while Trey Austin, Herb Baker and Terrance White added 16, 14 and 12, respectively.
Earl finished the evening 6-of-16 with 12 rebounds and six assists in 38 minutes of play.
Five Tiger turnovers led to an early 6-5 HSG lead before baskets by Torris Bright and Dupree put LSU ahead, 9-6, at the first media timeout.
LSU head coach John Brady, clearly unhappy with the play of his starters, quickly went to his bench, bringing in Jaime Lloreda, Tony Gipson, Charlie Thompson and Johnson before the period was less than halfway complete.
In one defining moment, after Temple lost a battle with Earl for a loose ball, Brady shouted, "You are so frickin' (ITAL) weak (ITAL)," a comment easily heard in the unusually quiet arena and greatly appreciated by the Tiger student section.
Temple responded on the next play by diving across the courtside seats in an attempt to corral a loose ball bouncing out of bounds.
The lineup change wasn't effective, however, as LSU coughed up four more turnovers in four minutes and held a slim four-point lead with 12 minutes to play in the half.
Johnson and Mitchell began to shine before intermission, with Johnson showing his range of athleticism. In his first appearance as a Tiger, Johnson turned a fast-break dish from Gipson into a three-point play, dropped in a jumper from the lane and slammed home a dunk to give LSU a 19-11 lead at the nine-minute mark.
"It was fun," Johnson said, "but after you get rid of the nervous feeling of it being your first game, you just have to give it all you got, bring something to the table, help the team win."
Mitchell entered the game and nailed his first shot attempt from the baseline. Mitchell was 4-for-6 from the field, including making 1 of 3 three-point attempts, and was a perfect 4-of-4 from the free-throw line.
"I think that Darrell and Shawnson played phenomenally," Temple said. "If it wasn't for Darrell in the second half, we would have been pretty stuck. But he stepped it up. A lot of times Ronald will tell me, ‘Everybody's not going to play well (all the time). Certain guys are going to have to step up to jump-start the team.' Darrell was that guy tonight."
"In my first game, I think I was overly nervous," Mitchell said of the previous exhibition game against Global Sports. "(Tonight) I just got into the groove, and felt more comfortable than I did in the first game."
A 9-0 LSU run was broken by four straight HSG points, but Mitchell answered with a pair of free throws and a basket to finish the half with a 41-32 LSU lead.
Senior forward Brad Bridgewater opened the second half with back-to-back power dunks, but LSU went cold and missed seven straight shots. White brought HSG to within three with a basket off of a Tiger turnover. Torris Bright sank a basket to end LSU's scoring woes, but a HSG 3-pointer by Austin off yet another LSU turnover tied the game at 49 with 12:21 to play in the contest.
The Tigers seemed to buckle down and play with a bit of consistency, going on a 16-4 run that featured a Mitchell three-pointer and four free throws by Temple.
Despite the win, Brady was unhappy with the results of a game that the Tigers should have won by a considerably larger margin.
"We're okay at times, but when we substitute a lot of guys we lose something," Brady said. "We're just not shooting the ball very well. That's one thing that hurts us. We miss quality shots, we miss open shots … It's bizarre, really, to watch it. We practice better than we play. We compete better against each other than we do in the game.
"We've got to transform some of our nice practices into play in a game. Because when we play somebody good, what we do now isn't going to be good enough.
"We have a long way to go," Temple said. "A long way to go to get where we want to be. And to get to where people expect us to be. And if we don't do that, we're going to be stuck with a whole lot of unrealized expectations."