William Somerville was delighted to help New Zealand battle back in the third Test against Pakistan - but admits they have plenty of work to do with the bat if they are to win the series decider.

Pakistan appeared on course for a large first-innings lead when they reached 286-3 at one stage on day three, Azhar Ali and Asad Shafiq both hitting centuries.

However, the Black Caps' bowlers restricted the deficit, taking the last seven wickets for 62 runs as they bowled their opponents out for 348.

Debutant Somerville led the way with 4-75 before returning to the middle before the close, coming out as a nightwatchman to keep captain Kane Williamson company as the tourists closed on 26-2, still trailing by 48.

"It's incredibly enjoyable just to be playing in my first Test, but it's nice that we've got ourselves into a decent position going into day four," he told the media.

"Obviously the game is in the balance - they were beautiful innings from Asad and Ali, it was very challenging bowling to those guys, but we've got ourselves into a good position."

Somerville was a late call-up to the New Zealand Test squad, his opportunity coming after Todd Astle was ruled out with a knee injury.

The 34-year-old - who ended his career in Australian domestic cricket for New South Wales earlier this year to return to the country of his birth - is hopeful his batsmen can now give him something to work with in the final innings.

Pakistan were unable to chase down 176 in the first Test at the same venue, though they squared the three-match series in Dubai with a comprehensive innings victory.

Asked how many his team will need to feel comfortable defending this time around, Somerville replied: "As many as we can get. 

"We're two down already, so we will be playing the long game and seeing how many we can get ahead.

"It's not easy to chase here - we know that. It's a good toss to have won.

"We've fought our way back into the match, which we are really happy with, but there's obviously a big couple of days to come in this Test."