Smith hit by Nortje bouncer, misses fielding duties on Day 4; Australia await update

During the first Test, Steve Smith took a blow to the helmet from Anrich Nortje.

Following a concussion evaluation on the field, he switched helmets and carried on to score 27 runs.

However, he was absent during South Africa's second innings.

With Cameron Green and Josh Inglis already sidelined due to injuries, the Australian team faces further challenges.

Updates on Smith's health are expected later today or tomorrow.