Le Roux’s 57th-minute try, which followed a try by prop WP Nel just three minutes earlier, came after the Cheetahs attacked from the restart, Ebersohn chipping over the defence and Le Roux then gathering and chipping again before reclaiming the ball and dashing over the tryline.
The Waratahs, who led 34-21 in the 48th minute after scoring four tries in the first half, can look back on a disappointing second half and their failure to use two late chances to claim victory. Flyhalf Berrick Barnes was short with an angled 55-metre penalty in the 76th minute and, as regular time came to an end, they had a maul inside the Cheetahs 22 and Barnes lined up for the drop goal. But they could not get the ball out as Cheetahs loose forwards Ashley Johnson and Heinrich Brussow did great work in keeping the ball off the ground.
The Cheetahs can threaten the best of sides with ball in hand, but their defence can be porous and the Waratahs took advantage of 18 missed tackles in the first half and particularly poor defence around the fringes to rush to the four-try bonus point in 33 minutes.
Flank Dave Dennis, who would be a thorn in the Cheetahs’ side all game, scored the first try in the fourth minute when he pounced on a loose ball behind the tryline, and he would be instrumental in the Waratahs’ next try just two minutes later when he burst clear from the kickoff and was only stopped inside the home side’s 22. From the resulting ruck, scrumhalf Brendan McKibbin found lock Sitaleki Timani on the charge and he powered through for the try.
The Cheetahs then drew level at 14-14 with two tries in four minutes. The first came from a wonderfully-worked move off a lineout as lock Izak van der Westhuizen fed Brussow, who linked up with Johnson charging through on the angle. The bushy-haired eighthman then found scrumhalf Piet van Zyl, who dotted down in the tackle.
Le Roux’s brilliant attacking running then started and finished a move in the 19th minute, with flyhalf Riaan Smit’s second successful conversion tying the scores at 14-14.
The Waratahs edged ahead again in the 22nd minute when McKibbin kicked a penalty after the Cheetahs took him out at a ruck, but his satisfaction turned to horror four minutes later when his pass was intercepted by hooker Adriaan Strauss and the Cheetahs captain ran in the try from halfway.
But the Cheetahs’ terrible defence saw them concede two tries in the last seven minutes of the first half.
Wing Drew Mitchell showed great skill to keep a kick in play, after which centre Adam Ashley-Cooper chipped ahead, the bounce was kind and the quick hands of McKibben put outside centre Rob Horne away on a 45-metre run to the tryline.
Timani then scored his second try, after good work by fullback Bernard Foley down the left touchline and eighthman Wycliff Palu at the kickoff, leaving the Cheetahs in need of a major turnaround.
Nel went low and hard to score for the Free Staters in the 54th minute, before Le Roux floored the Waratahs with another moment of brilliance three minutes later.
His moment of inspiration gave the Cheetahs their fifth win this season, the most they have achieved in a SuperRugby campaign.
Cheetahs – Tries: Piet van Zyl, Willie le Roux (2), Adriaan Strauss, WP Nel. Conversions: Riaan Smit (4), S. Ebersohn.
Waratahs – Tries: Dave Dennis, Sitaleki Timani (2), Rob Horne. Conversions: Brendan McKibbin (4). Penalties: McKibbin (2).