Mitchell Santner is set for a lengthly spell on the sidelines due to a knee injury.

Mitchell Santner, New Zealand's spin-bowling all-rounder, has been ruled out of cricket for six to nine months after a scan revealed he will require surgery on his right knee.



The 26-year-old had a scan during the recent T20I tri-series against Australia and England which revealed a bone defect, and a follow-up scan has shown the problem has worsened and will need surgery to be fixed.



Santner will be operated on this week, with a long period of rehabilitation to follow.



It comes as a cruel blow, particularly given his impressive performances in the 3-2 ODI series defeat to England in which he scored 216 runs at an average of 108, including a match-winning 45 not out in the first match in Hamilton. He followed that effort with 63 not out and a career-best 67 in losing causes in Mount Maunganui and Christchurch respectively.



Santner has also become a key player with the ball for the Black Caps, recently topping the MRF Tyres ICC T20I rankings.





Santner was in excellent form before injury struck



“On a personal level everyone feels for Mitchell," said New Zealand coach Mike Hesson. "He’s a popular guy in the changing room and he’s well respected for the work he puts in for the side.



"Mitchell is a key player in all three formats for us, so we’ll certainly miss him in the upcoming series. It’s important though that he gets this fixed and we have him back for what is a big next 18 months for us.”



Todd Astle, the Canterbury leg-spinner, has been called up in place of Santner for the upcoming two-Test series against England.