Rudolph’s steady 119 at the top of the order allowed Elgar to free the arms and show his big-hitting
ability in a knock of 98 from just 45 balls as the Titans amassed 330 for four.
Reeza Hendricks and Obus Pienaar struck half-centuries in reply, but the Knights lost too many wickets in the final 10 overs and were eventually bowled out for 309 to lose by 21 runs.
Rudolph anchored the innings after the Titans had won the toss and elected to bat, sharing a 77-run partnership with Henry Davids (51) up front before putting on 90 with Theunis de Bruyn (46) and 101 with Elgar.
It took an excellent piece of fielding off his own bowling from Quinton Friend to end Rudolph’s 135-ball knock, with the batsman attempting to steal a leg-bye only for Friend to throw down the stumps at the non-striker’s end.
Elgar continued his assault, however, reaching fifty in just 30 balls before motoring on to hit six sixes and nine fours.
The left-hander had a chance to reach three figures off the final ball of the innings, but was instead caught off the bowling of Shadley van Schalkwyk.
The Knights made a solid start to their reply, reaching 120 for one in the 19th over as Hendricks shot to 77 in just 54 balls.
However, the hosts stuttered after his run-out and struggled to regain momentum as wickets fell regularly, with Man of the Match Elgar taking a key wicket when he dismissed Pienaar for 63.
Dillon du Preez’s freewheeling 21 meant that the Knights still had a chance going into the final three overs, with 37 needed, but Marchant de Lange had him caught at long-on to end the resistance.
The result moved the Titans to within two points of the third-placed Lions, and left the Knights needing three wins from their last three games to keep pace in the competition.