South Sydney will need a last round win to secure a finals spot after a disappointing 29-10 defeat to the Knights in Newcastle.

Billed as the match of the round and the most important of the season for both sides with a finals spot on the line, South Sydney showed plenty of intent in their opening two sets to put in attacking kicks.

An errant second kick allowed the Knights to march downfield, and on the back of a penalty they took advantage of some poor defence to score through Greg Marzhew after six minutes.

Another defensive lapse saw Kalyn Ponga bust through the line and find Marzhew for his second inside the opening 13 minutes to give Newcastle an 8-0 lead.

They were able to stem the flow of points and get into the grind as a big crowd continued to get behind the home side through the middle stages of the first half.

Just as Tallis Duncan looked to have scored in the 29th minute, an obstruction from Tevita Tatola denied the Rabbitohs the chance to post their first points of the afternoon.

With time winding down in the first stanza, Souths were given a golden opportunity to attack after Duncan was hit high, but weren’t able to penetrate a staunch defensive line.

Newcastle had no such issues, again going down the left-hand side and finding Marzhew to bring up a hat-trick and send the Knights into the sheds up 12-0.

After a lacklustre first half, the Rabbitohs started the second in the best possible way, with Damien Cook taking the ball from the scrum at lock and taking on the defence, using his pace to bust the line and get his side on the board inside three minutes.

Damien Cook try 42nd minute

Just as they looked destined to cut further into the margin just moments later, a desperation tackle from Bradman Best denied Taane Milne over the line.

Despite getting back into the contest, Newcastle wrestled back the momentum with Daniel Saifiti getting on the end of a grubber to push the lead out to 18-4 with 23 minutes to play.

Their lead was extended in controversial fashion, with a loose ball touching referee Grant Atkins in the in-goal, but the Bunker confirming a try to Adam Clune to make the score 22-4.

Hope was starting to fade, but not before a strong burst from big Shaq Mitchell saw him overpower two defenders to score his first NRL try, and cut the margin back to 12 points with 13 minutes left.

That hope was soon removed after Best got on the end of an error to run 60m and put the Knights back up by 18 with less than 10 minutes remaining.

Shaquai Mitchell try 65th minute

Match snapshot

Play of the Game

With the Rabbitohs needing points coming into the back-end of the contest, big Shaquai Mitchell got across the line for his first try in the NRL, barging his way over two attempted tackles to keep Souths in the contest approaching the final 10 minutes.

Shaquai Mitchell try 65th minute

What's Next?

The Rabbitohs will get a week off to lick their wounds with a bye in round 26 ahead of a grudge match against the old rivals, the Roosters, at Accor Stadium in the final round. Depending on results, it could shape as a game where the winner advances to the finals and the loser misses out.

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