Root has struggled with the bat this year as England failed to regain the Ashes and were beaten in New Zealand, although he finally found his form with a double hundred in Hamilton.
Kallis, who has joined South Africa’s backroom team as batting consultant, admits the hosts will single out Root in a bid to heighten the scrutiny surrounding his captaincy.
“He’s under a bit of pressure but every captain goes through that,” Kallis told a press conference. They’ve kept him as captain so they obviously believe in him. We’ll certainly try to keep the pressure on him, and on England.
“It’s probably an area we will try and target and make sure we put as much pressure on him, but he’s a world-class player so just because he’s under pressure doesn’t mean he’s not going to have a good series. No doubt he will be up for a big fight and he’ll want to turn it round. We have to make sure we are on the ball against him.”
Kallis has linked up with old team-mates Graeme Smith and Mark Boucher, who have been appointed South Africa interim team director and head coach respectively.
The 44-year-old is widely regarded as one of the greatest all-rounders in history, and he believes England’s Ben Stokes is capable of reaching similar heights.
“He’s certainly got the talent to,” added Kallis. “I suppose it’s up to him how hungry he is and how far he wants to take his game.
“The one thing that’s been good is that he’s done it in a lot of formats and now he’s doing it in Test cricket as well, which is very pleasing to watch - it’s always nice seeing all-rounders come through.
“He’ll be a key player for them and we will have good strong plans against him with both bat and ball.”