But once the adrenalin starts to flow, he feels confident the jitters will go away – and he is confident Wigan can win.
Tomkins, 21, has enjoyed a remarkable transformation this season.

Last year, he was sent out to Widnes on loan, a two-month absence which meant he only managed three games in the Wigan first team.

This season he has become a stalwart in the back row, making 27 appearances and scoring 12 tries – including four against Hull in July.
And in the last eight games, he has made the pivotal loose forward place his own.

Tomkins said: "This is my biggest game so far. It's already been a massive step-up for me, and now we've made the last semi-final of the play-offs, this is the biggest step yet.

"I will be nervous, but the nerves will go as soon we get started.
"But I feel confident too. As long as we play as well as we have done in our last couple of games, I think we can do it.
"We might have to step it up a bit, but I think we can do that."
Leeds hooker Matt Diskin isn't thinking about Wigan.

He said: "We can't really worry about the opposition. All we can do is concentrate on ourselves and make sure we turn up in the right frame of mind.

"Yes we had an off-day against St Helens, but the disappointment has gone now.
"We have got to look forward and be positive.

"We're a talented team and if we concentrate on ourselves, we'll be good.
"In the last two years we've been through a lot of adversity and have been written off numerous times."
Brian Noble should name the same side that beat Catalans.

He said: "Other than Sean O'Loughlin and Paul Prescott, we have a clean bill of health and we need that as Rhinos will be coming at us with baseball bats.
"But I think we have a bit more energy than we had at this stage of the competition last year.

"We were using sticking plaster and brown paper to keep some of the guys on the field, but we don't have that problem this time around.
"The players are so keen to do well, but that's no guarantee that we will do well.

"We have to show up and match Rhinos for aggression and find a game plan to win."

Wigan: (from) Mathers, Calderwood, Goulding, Carmont, Richards, Barrett, Leuluai, Fielden, Higham, Paleaaesina, Hock, Bailey, Colbon, Coley, Hansen, Phelps, Tomkins,
O'Carroll, Smith

Leeds: (from) Webb, Donald, Senior, Smith, McGuire, Burrow, Leuluai, Diskin, Peacock , Jones-Buchanan, Ellis, Sinfield, Lauitiiti, Bailey, Scruton, Kirke, Ablett, Hall, Burgess