The pair has been 'feuding' since Robert first filled in for Sam last year, with fans begging the wildlife warrior to be Sunrise's permanent weather presenter.
Sam was on leave, with Robert doing the weather live from Australia Zoo and jokingly suggesting he was coming for Sam's job.
"We’re just going to up the ante, it’s just gonna get bigger and bigger and bigger," Robert said during his first live cross, where he introduced a tortoise from Australia Zoo, who happened to be named Sam.
"He’s a critically endangered elongated tortoise," he said. "Critically endangered ... a bit like Sam Mac’s career at the moment."
Monique Wright, who was filling in for Natalie Barr, and Matt 'Shirvo' Shirvington joked that Robert was winning in their 'feud'.
"Robert 1, Sam 0," Shirvo said.
"But, no, he really is beautiful and just, oh, mate, we love him," Robert said of the tortoise.
It comes after Sam shared a photo with a Sunrise viewer who was holding a sign that read: "Robert Irwin 4 Weather Man."
Robert commented on the photo, "What do we think guys, do we need a petition??"
"It’s live right now my friend* (*=nemesis)," Sam joked.
During the live cross where Sam first noticed the sign he joked, "And just when you think that you’re welcome in a town, you notice this sign. Tara — that’s very, very generous of you to bring that this morning when I felt everyone loved me here.
"Not only has he got the new girlfriend now, he’s hijacking my segments when he’s not even here. Do you want me to come back with a crocodile? Is that what you guys want?
"I'll do it. [Australia Zoo] is just down the road," he quipped.
Thankfully, Sam's fans don't want to see him leave the show, with many sharing their support on Instagram.
"No way, Robert is lovely, but will always love Sam as our weatherman!" one fan said.
"This is gold but I’m a Sam lady myself," another added.
"Sam is a great weatherman always entertaining," a third said. "Keep up the great work. Brings a smile to my face every morning."
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