England coach Eddie Jones backed Owen Farrell to avoid being cited for a unsafe tackle that could rule him out of next week's clash with New Zealand as he turned on his critics following a nail-biting 12-11 win over South Africa on Saturday.
Gloucester number eight Ben Morgan has not been considered for the second Autumn International due to injury.
"He's going for an examination now [Monday afternoon] and the news probably isn't going to be too good".
Wasps flanker Shields will face the country of his birth in England colours this weekend when the All Blacks arrive at Twickenham to take on Eddie Jones' side.
Farrell, who was yellow-carded for a similar hit late in the defeat by Australia that ended England's World Cup hopes in 2015, could still be punished if the citing commissioner deems Saturday's hit worthy of a red card. You're going to do it at some stage.
"What we've got to do is make sure we play like England, do everything we can to maximise our game, look at areas where New Zealand are weak and see if we can find a way to expose those weaknesses", he told BBC Sport.
"He injured his ankle but beyond that we don't know how long, but for the next three Test matches he'll be unavailable for us - everybody else is available for selection". "We didn't give", Jones said.
"We are asking one referee to do it the way they did it when blokes like me were playing - jogging round the field basically".
"New Zealand's a different kettle of fish to the Springboks", said Jones, Australia's coach when they lost the 2003 World Cup final to England in Sydney and a consultant to the 2007 world champion Springboks.