Late goals by Tshidiso Tukane and Matthew Rusike saved some face for Jomo Sono’s men after Mongezi Bobe’s brace had put Lido Duvha ahead.
The relegation is Sono’s third in row in the top-flight, but it could have started so much more positive but for Katlego Loke’s shot hitting the post.
In the 16th minute Cosmos had another opportunity when a shot by Matthew Rusike went over the bar, with Bobe following suit two minutes later.
Avril Phali saved from Ernort Dzaga just before the break, while Bobe again fired over to send the teams into the break on level terms.
Cosmos fell behind the 72nd minute after great work from Raymond Monama on the left as he beat a defender before sending the ball into the area, where Bobe made no mistake.
Leopards doubled their lead four minutes later; Bobe controlled the ball on the edge of the box before unleashing a curling left-footed shot that beat Phali.
The match had seemed won by Leopards, but the Ezenkosi pulled one back six minutes from time.
Tukane, who had only just came on as a substitute two minutes earlier, got Cosmos back into the match as he slotted home from a goalmouth scramble.
Four minutes later, Siyabonga Nhlapo showed good vision as he found Rusike, who beat the offside trap and the Leopards keeper to make it 2-2.
Cosmos have now been automatically relegated from the PSL for the third consecutive time, whilst Leopards are not safe yet as they are only two points ahead of Santos in the fight for survival and try to avoid the relegation/promotion play-offs.