De Lange picked up five wickets on the final day to record figures of 6 for 108 as the Knights were bowled out for 396 in their chase of an unlikely 549.
Pite van Biljon’s century and 68 from Obus Pienaar helped the Knights put up the highest score of the match in the fourth innings, but in the end they paid for a poor start to the game, which was in some respects understandable given how little time they had to switch formats after reaching the RAM SLAM T20 Final last Friday.
The hosts went into the final day on 180 for three with Rudi Second and Van Biljon entrenched on 76 and 73, but De Lange removed Second (80) in the third over of the day to make the crucial breakthrough.
Van Biljon went on to his eight first-class century and shared a 68-run stand with Pienaar to keep the Titans honest, before falling to the leg-spin of Shaun von Berg for 113.
Pienaar was joined by Werner Coetsee for another lengthy partnership that ate up 19 overs and brought 68 runs, but the second new ball did the trick as Rowan Richards dismissed Pienaar to grab his third wicket of the innings and eighth of the match.
De Lange went on to strike three times in three overs as the Knights finally folded and impressively took only a brief break that incorporated a change of ends in the course of sending down 10 overs after the new ball was taken.
The Titans now lie second on the table after picking up 19.32 points from their second win of the competition, while the Knights are third after earning 5.7.
The scoreboard (Supplied by Sapa):
Titans first innings 366
Knights first innings 185
Titans second innings 367/7 declared
Knights second innings (o/n 180/3)
GL Cloete c Mosehle b Richards 22
RR Hendricks c Mosehle b Richards 3
GJ Abrahams c Mosehle b de Lange 0
RS Second c Mosehle b de Lange 80
PJ van Biljon c Wiese b von Berg 113
AJ Pienaar c Behardien b Richards 68
WL Coetsee c Davids b de Lange 39
MP Siboto c Kuhn b de Lange 15
D Olivier c Mosehle b de Lange 4
Q Friend b de Lange 29
LMG Masekela not out 6
Extras: (b12, lb3, w2) 17
Total: (all out) 396 -- 101.5 overs
Fall of wickets: 1-12 (Hendricks), 2-13 (Abrahams), 3-42 (Cloete), 4-186 (Second), 5-254 (van Biljon), 6-322 (Pienaar), 7-351 (Coetsee), 8-356 (Siboto), 9-375 (Olivier), 10-396 (Friend)
Bowling: De Lange 27.5-2-108-6 (1w), Richards 22-3-79-3 (1w), Dala 14-2-64-0, Von Berg 26-5-89-1, Wiese 9-1-32-0, Davids 1-0-2-0, Van der Merwe 2-0-7-0
Result: Titans won by 152 runs
Points: Titans 19.32, Knights 5.7
Player of the match: RR Richards (Titans).