The flanker crossed with nine minutes to play after Ryno Benjamin’s 65th minute score had briefly given the visitors hope in a game that lacked any energy or zeal.
Eleven of the home side’s other points came via the boot of Frans Steyn during the second half, but coach Jake White will be pleased after his side moved six points clear at the summit despite their unimpressive display on the east coast.
Tim Swiel, making his full debut, was in the thick of the action early on squandering a chance to settle any nerves by missing a penalty and then making a darting run through a hole, only to deliver a wayward pass.
At the other end, Elgar Watts was much more accurate with his first kick at goal, following an off-side call against the hosts, as the Cheetahs led after five minutes.
Both sides then appeared to drift into slow motion with no further points coming for over 25 minutes.
There were a few moments of excitement for the hosts in that period, though, with another debutant Tonderai Chavhanga showing promising signs down the left.
The Sharks finally had their first points in the 34th minute when the visitors were punished for not releasing and Swiel found his range.
Another kickable penalty followed for side entry against Jean Cook, but the Sharks opted to set up a line-out that came to nothing.
Then on the half-time hooter Swiel missed another straightforward kick. He missed to the left after Heinrich Brussow was punished for not releasing, leaving the sides all square at the break.
The Sharks took the lead for the first time six minutes into the second half when kicking duty shifted to Steyn, who knocked over his first chance after Maks Van Dyk was penalised for illegal scrumming by referee Jaco Peyper.
They went even further ahead another six minutes on when Boom Prinsloo was called for collapsing a maul and Steyn banged over a monstrous 45-metre penalty.
The visitors were reduced to 14-men just after the hour as Brussow was yellow carded for hands constantly in the ruck after Cook had initially inexplicably knocked on right in front of goal with Steyn making it 12-3 from right in front.
However, there was a response to come from the Cheetahs, and after Watts missed a penalty from distance, Benjamin crossed for a try on the left when Steyn’s attempted clearance was charged down by Hennie Daniller.
Watts missed the subsequent conversion, although it was a four-point ball game with 14 minutes to play.
But Deysel ended any hopes of an upset when he went over on the left after Swiel initially carved open the defence by running through a hole in the visiting backline.
Scorers: Sharks: Try: Jean Deysel. Conversion: Frans Steyn. Penalties: Tim Swiel, Steyn (3).