New Zealand's injury crisis has been compounded with confirmation that fast bowler Will O'Rourke has been diagnosed with a stress fracture in his lower back.

O'Rourke last featured for New Zealand in their clean sweep Test series against Zimbabwe, but reportedly felt stiffness in his back on the third day of the opener.

The 24-year-old will now miss the Black Caps' limited-overs series against Australia, England and the West Indies, though he could also be a doubt for the three Tests that follow against the Windies.

New Zealand coach Rob Walter is hopeful O'Rourke can avoid surgery, with the fast bowler set to undergo a three-month conditioning and rehabilitation program.

"We're really feeling for Will at the moment and wishing him a speedy recovery," Walter said in an NZC release.

"He's had such an impressive start to his career, and so naturally it is disappointing when an injury like this comes along, but he's a resilient guy and determined to put the work in and come back stronger.

"We're very hopeful for that [three-month time frame]. Stress fractures are obviously almost part and parcel of the craft, really, but never nice when it does happen.

"At this stage, we will reassess after that three-month mark, hopefully the healing process has gone really well, and we can get into that return to play."

Injury Updates: Will O'Rourke will be out of action for at least three months after scans revealed a stress fracture in his lower back.

Glenn Phillips (groin injury) and Finn Allen (foot injury) have also been ruled out of the upcoming Chappell-Hadlee series as they continue to… pic.twitter.com/bs2rHjD7fh

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O'Rourke's setback comes amid a mounting injury crisis for the Black Caps.

Finn Allen is also facing a lengthy spell on the sidelines with injury, while all-rounder Glenn Phillips and captain Mitchell Santner remain doubtful for New Zealand's T20I series against Australia at the start of October.

Phillips did not feature in either of the two Tests against Zimbabwe due to a groin injury, while Allen has had surgery on a stress fracture in his right foot, which will require three months' recovery.

Santner, however, could be back in action sooner than expected, with Walter confirming that his recovery from a groin injury sustained during the ongoing Hundred is progressing well.

"Mitch is a world-class player and a crucial part of our T20 side from a skills and leadership point of view," Walter added.

"With that in mind, we expect to name him in our squad when we announce it in a couple of weeks' time, and from there we can assess how his rest and rehabilitation progresses following surgery, before making a call on the eve of the series."

Walter added that the loss of Allen and Phillips - both important batting contributors - will be felt, but it also presents opportunities for other players to step up.

"It's disappointing to lose the services of Glenn and Finn, who have played important batting roles in our T20 set up in recent times.

"But like in Zimbabwe, their unavailability will present opportunities for others to put their hands up in what's going to be a hugely exciting and important series against Australia."