Leeds scored five first half tries to lead 26-0 at half time but the Rabbitohs hit back after the break to push the Rhinos all the way.
The Rhinos kicked off at Hodges Stadium in cold conditions but with the rain from earlier having eased off.
The pre-match hype could have become a distraction for the Rhinos as the Russell Crowe show rolled into to town but they made the best possible start when they scored the opening try through Matt Diskin. There was an element of good fortune when Gareth Ellis' offload was knocked back over the line by the Souths defender and Matt Diskin was on hand to touch the ball down. Kevin Sinfield added the conversion to make it 6-0.
The Rhinos doubled their lead after 16 minutes when Lee Smith intercepted a looping pass ten metres from his own line. He offloaded to Clinton Toopi, who released Brent Webb to race 80 metres up field and score. Sinfield converted the try to make it 12-0.
Leeds had another great chance three minutes later when Jamie Peacock produced a monster hit on Jaiman Lowe that turned over possession. Danny McGuire burst clear but was just stopped by the last defender.
Both teams had a short two minute break after 20 minutes to take on water but the Rhinos continued their dominance at the re-start. McGuire put in the initial kick and it was hacked ahead by Diskin before Rob Burrow raced through to touch the ball down. Sinfield added his third goal to make it 18-0 after 22 minutes.
The onslaught continued after 26 minutes when Keith Senior made the extra man out wide and powered his way over from close range. Sinfield was unable to add the conversion but the Rhinos now led 22-0.
The Rhinos made a perfect finish to the first half with a try in the last second. Luke Burgess gave the move momentum with a crashing run in midfield before offloading to Burrow. He arced across the field before grubber kicking to the corner. Senior was taken out as he went for the ball but Scott Donald was in support to score the try. Sinfield missed the touchline conversion but the Rhinos now led 26-0 at half time.
Brian McClennan made a host of changes at half time with next weeks game against Hull KR in mind. The disruption took time for Leeds to settle back into their defensive pattern and the Rabbitohs took advantage with two tries.
Prop Michael Greenfield burst through to set up the first try which was scored by stand off Ben Rogers. Then, after 54 minutes, hooker Issac Luke burst through some poor defence to score. Eddie Paea converted both tries to make it 26-12 to the Rhinos.
The Rhinos had a try disallowed for Senior after a great offload by Ali Lauitiiti however the Great Britain international was only just able to get the ball down before he went out of play.
Souths went down the other end of the field and nearly added a third try just before the hour mark but it took a great cover tackle and good support by Senior to snuff out the chance.
However, Souths did get their third try with 17 minutes remaining when Eddie Paea stepped his way through the Leeds defence to score between the posts. Issac Luke added the extras to make it 26-18.
It looked like Souths would score a certain try with 11 minutes remaining when Paea broke through again but it took an incredible tackle by Nick Scruton to stop him, who then rolled under the ball to stop him getting the ball down.
Leeds held their line well and ran down the clock so that when Souths did score through George Ndaira it could not effect the result. The same converted his own try to make the final score 26-24 to the Rhinos and capped a worthwhile trip to Florida for Brian McClennan and his side.