NSW Waratahs lock Rob Simmons has warned how lethal the Melbourne Rebels combination of Will Genia and Quade Cooper can be, as he prepares to face his old teammates in a pivotal Super Rugby matchup.
The Australian Conference-leading Rebels go into Saturday's SCG clash seven points clear of the second-placed Tahs.
Simmons has played alongside halfback Genia and five-eighth Cooper for much of his provincial and Test career, with all three of them starting in the Queensland Reds' 2011 Super Rugby final win over the Crusaders.
"You end up playing against a lot of your mates and that's a fact of professional rugby; people move around and it's an enjoyable thing too," Simmons said.
With Reds' coach Brad Thorn placing an emphasis on youth, the three veterans have found new clubs, with Simmons on the opposing side to the playmaking duo.
"I know them very well and how lethal they can be," Simmons said.
"Will and Quade can pick a misread and if you crumble under pressure then they can put someone away behind your goalposts.
"It looks like they are back on the page that they know so well."
The lineout looms as a key battleground with the Rebels boasting the competition's highest success rate of 94 per cent and the Waratahs third on 92.
"It's going to be a good battle this weekend, because they've improved a lot on their defensive lineout," Simmons said.
Simmons will come up against one of Australia's other top locks in Adam Coleman.
"He's been playing very well also, but I think as a group we've got to all stand up, their pack has been going quite well" Simmons said.
He believes the Stormers' performance in their win against the Rebels in Melbourne last week offered the Tahs some clues.
"They shut down their front-foot ball, they (Melbourne) probably got a little bit outworked there and then they lost their way after that," Simmons said.
Unlike several of the Tahs' other Wallabies, Simmons has yet to be rested from a game this year.
"I'm not really looking for a rest, it's only halfway through a season," he said.
Waratahs coach Daryl Gibson is expected to make at least three changes to his side, with Israel Folau unavailable, Ned Hanigan injured and Michael Hooper back after being rested.