The Maroons mentor delivered a huge rap to Broncos flyer Corey Oates, who Murray Taulagi beat for the vacant Queensland wing, but he insisted the Cowboys gun deserved his shot in Perth.
Taulagi will make his Queensland debut on Sunday night after Melbourne speedster Xavier Coates suffered an ankle injury in game one.
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Taulagi will cover the Maroons' left wing as Broncos whiz-kid Selwyn Cobbo retains his spot on the right – and Slater is at ease with the selection call.
"I think they've both earned their spot in this squad. Murray was in the 22 for game one and I said right from the start that those five guys outside the 17 weren't here for an experience or weren't here for a holiday; they were here because they'd earned the opportunity to be here and they were next in line," Slater told Nine's 100% Footy in a cross from the Maroons camp.
"(Taulagi) was really close for selection in game one. He's been doing tremendous things up there at the Cowboys and been a big part of why they're having a successful year. Through his actions he's earned his opportunity. He's going to be next to Valentine Holmes (who) he plays next to every week, so that's a bonus. Murray's certainly earned his opportunity."
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Taulagi has snared nine tries from 15 games this season and produced some superlative finishes.
He also set up a Cowboys try with an otherworldly pass in Magic Round, hurling the footy back in while airborne over the left touchline to set up a Scott Drinkwater four-pointer.
Wests Tigers halfback Jackson Hastings was wrestling with Taulagi in a desperate bid to tackle him into touch, but that didn't stop the red-hot talent from landing the ball right in Drinkwater's mitts.
Cowboys weapon Hamiso Tabuai-Fidow had been jostling with Taulagi and Oates for the Maroons' available wing spot, but he failed a head injury assessment during North Queensland's win against Manly last Friday night.
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Slater suggested it was a tight race between Taulagi and Oates, who's bagged 12 tries in 14 games this season.
"I don't know if I've seen Corey play better football, and he has played for Queensland, so he's right there abouts, as well," Slater said.
"I think we're pretty comfortable with our starting 17, but those five guys that are outside it – they're here for a reason."
North Queensland's Tom Dearden, Brisbane's Oates and Thomas Flegler, Gold Coast's Beau Fermor and the Warriors' Reece Walsh make up the Maroons' extended squad.
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