"It seems they referee Randle differently than Casey," Gleeson said. "We've asked why [but] nothing gets done. It's a waste of time [asking again].
"Maybe Casey's stronger and takes the hit to keep going. We had that call go against us, Casey's charge foul, which looked to me to be two points.
"It's hard when two [36ers] players get 23 foul shots, and we're just as aggressive and nothing gets done, then Casey gets pole-axed at the end.
"It's frustrating for Casey. He's pretty banged up.
"The game was (won) on the foul line ... a 30-19 foul count, 36-16 fouls shots - it's pretty hard to defend foul shots."
Gleeson did acknowledge the ladder-leading Sixers (11-6), now riding an eight-game winning streak, as the league's benchmark in an otherwise congested table.
"They've got a good buffer," he said. "Normally 14-15 [wins] gets you into the playoffs.
"They're playing at a good level and they're getting to the foul line a lot, which is hard to defend."