New Zealand skipper Daniel Vettori needed two stitches to the forefinger on his left hand on day two at Essex.
The spinner hurt his bowling hand backing up as the hosts replied to 355 with 251-9, but x-rays showed no break.
England batsman Alastair Cook, who disclocated a finger while fielding on Friday, was cleared to bat but after two fours he edged behind for 15.
"It didn't hinder my batting, and once the swelling goes down in a couple of days I'll be fine," he told BBC Essex.
"I've had three knocks now and obviously haven't got many runs which is disappointing but hopefully it comes right in a couple of weeks time."
Vettori is expected to be fit for the first Test on 15 May but is unlikely to play any further part in this match, and is also set to miss the team's final warm-up match against England Lions at the Rose Bowl starting on Thursday.
Team manager Lindsay Crocker explained: "He's cut the first knuckle, at the top, across it on the underside of the finger.
"There was a bit of blood but we thought maybe he might have done some other damage - so we wanted to get it x-rayed to see maybe whether there was a problem with the tendon or bone.
"But there are none of those - it's just a soft-tissue split and he's had two stitches.
"He should have the stitches out in about a week and should be fine."
England hopeful Ravi Bopara hit nine fours in an attractive 66 but was the first of three wickets to fall in two overs for one run during the afternoon.
Cook did not take the field when New Zealand resumed in sunny conditions on the final morning at 348-9.
Their innings continued a mere seven deliveries as Ten Doeschate struck with his first delivery, trapping Mason lbw pushing forward to record his best figures for Essex.
Mason then enhanced his claims for a place in the New Zealand attack at Lord's for the first Test on 15 May when he dismissed both Essex openers before lunch.
He trapped Jason Gallian on the line off-stump and then Cook got an outside edge which just carried to wicket-keeper Brendon McCullum.
Bopara struck his first ball gloriously through mid-on for four off Mason and played nicely before he picked out short cover with a back-foot drive off Iain O'Brien, who began to generate some dangerous reverse swing.
It led to a mini-collapse, Ten Doeschate falling for a single to a catch at bat and pad off Vettori, and Pettini's middle stump uprooted by O'Brien.
The Kiwi skipper was then sidelined as he stopped a throw from McCullum after tea.
Essex needed a partnership and it came from Alex Tudor and Tony Palladino.
Tudor, who made 99 in a Test against New Zealand in 1999, hit six fours but fell nine short of fifty when McCullum snared an athletic catch.
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