Ross Taylor's eyes have been blamed for his continued form struggles in test cricket, and may see a new batsman picked for Friday's test in Hamilton.

After reinventing himself as an opening batsman, Dean Brownlie is a chance of playing his first cricket test in three years back in the New Zealand middle order.

Instead of captaining Northern Districts in the Plunket Shield in Napier on Tuesday, the 32-year-old batsman was added to the Black Caps squad as cover for senior man Ross Taylor whose eye problems continue to cause concern.

It means potentially two changes to the New Zealand XI for Friday's second and final test against Pakistan in Hamilton, with spin bowling allrounder Mitchell Santner returning to the squad after making a speedy recovery from a fractured left wrist suffered three weeks ago.

ANDY JACKSON/FAIRFAX NZ Northern Districts opener Dean Brownlie played his last test in May 2013 in the middle order in England.

He came in for Jimmy Neesham who was unwanted for the eight-wicket win in Christchurch, and will likely edge out legspinner Todd Astle who played his first test in four years at Hagley Oval.

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Taylor was expected to be ruled out after he saw an eye specialist in Christchurch on Monday, but will instead get a second opinion in Auckland before a decision is made on whether he plays his 78th test.

REUTERS One of the players of the India tour, Mitchell Santner has returned to the Black Caps squad after suffering a broken wrist.

Captain Kane Williamson described it as a growth in Taylor's eye that had gradually affected his vision, after his run of test innings without a half-century extended to 10 in Christchurch. Known as a pterygium or surfer's eye, Taylor spoke of the problem a year ago when he visited a Brisbane optometrist and was prescribed drops which helped him plunder 290 in his next test innings against Australia in Perth.

The Black Caps are certainly in a good position to gamble on Taylor at 1-0 up in the series, but will have to weigh up whether he's best served having a short break or trying to get a score under his belt ahead of the Chappell-Hadlee ODI series in Australia starting on December 4.

"We're still waiting on a little more information on Ross before we make any decision on his availability for the second test. Dean will come in as cover, but we should know more in the next couple of days," selector Gavin Larsen said.

Larsen and coach Mike Hesson, after nailing it with the introduction of Colin de Grandhomme and Jeet Raval in Christchurch, had plenty of headaches trying to select middle order cover for Taylor.

They settled on Brownlie who averaged 29.62 in 14 tests, the most recent against England in May 2013. A strong back foot player, he excelled in the middle order in Australia and South Africa then tried his luck as an opener with reasonable success in domestic cricket.

His 143 for Northern against Auckland at Mt Maunganui last week may have swung Hesson, even if he is usually reluctant to switch someone from their familiar spot.

There was also a distinct lack of middle order contenders in domestic cricket. Central Districts' Will Young looked next cab off the rank and was selected for New Zealand A against Pakistan but in five first-class innings has a best of 52 this season.

Northern's Bharat Popli, the domestic batsman of last season, scored even fewer runs than Young while Wellington's Luke Ronchi hasn't batted for a month after being the Black Caps' highest test runscorer in spin-friendly India then being dropped from the ODI team. Corey Anderson (back) wasn't considered as a stop-gap and neither was Martin Guptill as he rests a right shoulder injury ahead of the Chappell-Hadlee series.

One of the players of the India tour, Santner's return will likely mean bad news for Astle on a Seddon Park pitch that has been a lot bouncier and seamer-friendly in the past year with its new clay on one side of the block.

"With him [Santner] and Todd in the team, it gives us the opportunity to play two spinners if required. Mitchell brings all-round ability and is coming off a strong tour of India," Larsen said.

New Zealand test squad for Hamilton: Kane Williamson (captain), Tom Latham, Jeet Raval, Ross Taylor/Dean Brownlie, Henry Nicholls, Colin de Grandhomme, BJ Watling, Mitchell Santner, Todd Astle, Tim Southee, Neil Wagner, Trent Boult, Matt Henry.