Toss Crucial On Grassy Dunedin Deck

If Brendon McCullum can get the toss right, he'll be unleashing Tim Southee and Trent Boult on the first morning of the first test against Sri Lanka in Dunedin today.

The Black Caps skipper says the grass on the deck means an extra seamer in Neil Wagner is a real chance for his first test in a year.

"I expect it should have a bit of pace early on, probably a little bit of seam movement as well, but you've just got to make sure the team that you're picking isn't for the first day, it's for the full five days."

Mitchell Santner will earn his second test cap today, named to back up from Adelaide.

The Northern Districts allrounder will again bat six, but may not have Mark Craig as a spin partner.

McCullum said Santner will play a big role with bat and ball.

"Depending on which way we go he's going to have a pretty vital role with the ball too, he's an incredibly unflappable character for such a young guy."

If Sri Lanka lose the toss, captain Angelo Mathews said they have to knuckle down.

"You can't really control the toss, if you have to bat first you've got to do it. And it's just the mindset, we've got to take up the challenge and try and score runs on that wicket."

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