The Wolves only have a remote chance of avoiding finishing in the bottom-four when the season splits for the Super-8s.
They would need to win their remaining two games and hope Huddersfield lose to Leigh and Hull FC.
Despite their faint survival prospects, Tomkins believes they will be keen to show they can still be a force.
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He said: “I was thinking about it today.
“If I was in their position and probably not making the eight, I’d think, ‘We have to set a standard here and show we’re better than this’. They’ll want to come and prove a point. We’ll be in the Super-8s and we’re in the Challenge Cup semis, and they’ll want to get a score and take two points off us.
“Tony Smith is a great coach and, as players, they’ll be thinking, ‘We want to prove some people wrong’.”
Tomkins made his return from injury against Warrington last month, and scored the decisive drop-goal in a Cup quarter-final victory.
“I never genuinely thought they’d be in the middle-8s, but that’s the way it is,” he said.
“It’s just not gone for them, but look at what happened to Leeds last year, and now they’re one of the best teams in the competition.
“I imagine they’ll want to take a leaf out of their book.
“If they are in the middle-8s, I’d be surprised if they lost any games.”
The Super-8s concept is now in its third year but there has been no confirmation what structure 2018 will take - or how many clubs will be in the top-flight.
“The best structure I’ve played under is this one,” said Tomkins.
“The RFL have a tough job coming up with a system which keeps everyone happy, and that’s the way it is because there are so many clubs and different sets of fans.
“With this, it puts everyone under scrutiny.”
Wigan have not lost since Tomkins returned and a victory tonight would cut the gap on the top-four to two points, ahead of the completion of round 22 fixtures.
The 28-year-old full-back admits he has enjoyed the fact many have already dismissed the Warriors’ Grand Final chances.
“I love being written off,” he added. “What is in every rugby league player is a competitiveness - everyone wants to win games, and when you’re getting criticised for your will-to-win, all it does is give you a bit of defiance.”
Wigan have extra motivation to get the victory tonight – to ensure the Wolves don’t dampen Sean O’Loughlin’s 400th appearance for the club.
“He’s an inspiration, he leads by actions, he’s right up there with the best players I’ve played with,” added Tomkins.