But allrounder Jacques Kallis felt there was still plenty of time left, with two extended days' play, and enough moisture in the wicket to ensure a result was highly possible.
"It has quickened up a bit. It is a good Test wicket. There is a bit in it for the fast bowlers when they get the ball in the right area," Kallis said on Sunday night.
"Tomorrow morning is a key period.
"I think we have to give ourselves an opportunity, the game is far from dead."
Kallis admitted Clarke's early wicket would be an important domino to fall.
"That's massive, any wickets we can get tomorrow morning will put them right on the back foot," he said.
"Obviously he's a world-class player and he's shown that, he's a vital wicket for us but we (also) need to pick up a few more."
- AAP