The 19-year-old Powell will get his chance in the absence of Australian stand-off Brett Finch, who has been ruled out with a hamstring injury sustained in last Friday's 40-16 win over Castleford.
Powell, who has come through the ranks at Wigan, would have had a run earlier this season but for breaking a leg in the under-20s and Wane is predicting a big future for him.
"I'm excited to see how he goes," Wane said.
"If he hadn't broken his leg, I'd have rested Finchy and Tommy Leuluai before now and played him because he's the next in and he'll be playing next year.
"He's a Wigan-born lad and he's a great kid to have around. He loves being coached by us and always wants information from us.
"He's very skilful and defensively he's tough. It's his debut so I'm not going to pile a load of pressure on him but I expect him to do a halves' job which is to direct us around the park."
Finch, who is returning to Australia at the end of the season, will miss his first Super League game of the season after damaging a hamstring.
"He kept quiet about it and told us about it after the game," said Wane. "That was special."
Finch captained the Warriors against Castleford in the absence of loose forward Sean O'Loughlin, who is still struggling to get over his hamstring injury.
"It's not really cleared up," added Wane. "If something was to go wrong, it would be six weeks and I'm not prepared to risk that."
Wane said he had no hesitation in handing the captaincy to the 23-year-old Tomkins.
"I see Sam as our long-term captain when Lockers moves to one side," he said. "Sam is a Wigan-born lad and loves it here.
"He's a good leader, he inspires people so I'm comfortable making him captain. I've no concern about his age whatsoever. He was ready for it two years ago. He's a very old head on him."
Wigan will also be without forward Ben Flower, who pulled a hamstring against the Tigers, and centre Darrell Goulding, who was unconscious for two minutes after taking a head knock last Friday.
"He's not good," said Wane. "He's worse today than he was after the game."
Meanwhile, Wane is expecting the Rugby Football League to charge Castleford hooker Ryan Hudson with biting.
Tomkins complained to referee George Stokes about the bite during Friday's game and the RFL have asked Wigan for more information.
"They asked us for any photographic evidence that we had but the referee saw it on the night," Wane said. "We've sent them what we've got.
"If one of my players did that, they wouldn't need suspending - I would not accept it. I am surprised he's done that. Ryan Hudson is a good professional, he must have had a brain explosion."