The 26-year-old former Black Cap was struck on the helmet by a bouncer from Scott Kuggeleijn during a Plunket Shield match at the University Oval in mid-February.
While he continued with his innings, he began to feel ill and was unable to field later in the day and during the final day's play.
He was named in the Otago squad for the game against Auckland two weeks ago but missed the match because he was still feeling unwell.
A request to interview Rutherford was declined but Otago coach Nathan King said the aggressive left-hander was still getting headaches and would not be considered until he was free of symptoms.
‘‘He is having some good days but there are days where he does feel headaches,'' King said.
‘‘I think he wants to give himself some time where he actually feels good about things because, up in Auckland, he had a couple of good days and did some light exercise and the following days he had a headache.
‘‘It is not like a normal injury, where you feel good one day and you know you are over it and it won't come back again.
‘‘It is completely different from any other injury.
‘‘We just keep saying, hopefully it does not take too long and he is back on the field playing.''
Fellow opener Brad Wilson captained the side in Auckland and will remain in the role. Black Caps off-spinner Mark Craig replaces leg-spinner Rhys Phillips in an otherwise unchanged 12.
Otago is in last place in the tournament with 42 points from six games. Auckland leads the competition with 85 points from Canterbury on 71 points. Wellington (67) is reasonably well placed but Northern Districts (49) and Central Districts (48) have plenty of ground to make up in the remaining four games.
Wilson has been Otago's most productive first-class batsman with 646 runs at an average of 53.83. Only Northern Districts player Bharat Popli has scored more runs this season.
Neil Broom has been in good touch as well. He needs another 15 runs to register 500 runs in the campaign.
The bowling attack has lacked some potency, though. The Volts do not have anyone in the top 15 wicket-takers. Sam Wells and Jacob Duffy have 13 apiece, which places them 17th and 18th respectively.
Twenty-year-old Jack Hunter has shown some promise in his rookie season with 12 wickets at 32.44. He lacks a little pace but is dangerous when the ball is swinging.
Plunket Shield
Otago v Canterbury
Otago: Brad Wilson (captain), Anaru Kitchen, Michael Bracewell, Neil Broom, Jimmy Neesham, Derek de Boorder, Sam Wells, Mark Craig, Craig Smith, Jacob Duffy, Jack Hunter, Christi Viljoen.
