In case you thought it was dead......

Corné Steenkamp of the Pumas picks up a loose ball and drives ahead. Werner Kruger of the Blue Bulls grabs him and the two go to ground. Four Puma players gather over Steenkamp. The ball is on the ground below them and John-Cecil Kemp of the Pumas reaches down with a long arm and picks up the ball.

The referee penalises him, saying that he was not allowed to use his hands in a ruck, which he had done by picking up the ball.

Hands in a ruck! You may have thought it had gone the way of foot-up and a straight scrum feed, but apparently not.

16.4 (b) Players must not handle the ball in a ruck except after a tackle if they are on their feet and have their hands on the ball before the ruck is formed.
Sanction: Penalty kick

That's clear. If this was a ruck, Kemp was penalisable.

If.

What constitutes a ruck?

Law 16 DEFINITIONS
A ruck is a phase of play where one or more players from each team, who are on their feet, in physical contact, close around the ball on the ground. Open play has ended.

There are Pumas and they are on their feet, but is there a Blue Bull in physical contact closing round the ball on the ground?

The ball is on the ground but Kruger is certainly not on his feet.

Juandré Kruger is standing at the back of the group of players with a hand lightly on a Puma. He is certainly not closing round the ball and his physical contact is too tenuous to count.

If that were the case it would seem that if there was no ruck play should have gone on.

If.

Then there is the International Rugby Board's Ruling 3 of the 2007.

Request

A ruck is formed and the ball is playable for Team A. All players in Team B now leave the ruck and step back. Is there still a ruck or has the ruck ended?

Ruling of the Designated Members of the Rugby Committee

A ruck ends successfully when the ball leaves the ruck or when the ball enters in goal i.e. on or over the goal line.

A ruck ends unsuccessfully when the ball becomes unplayable.

As there has been a ruck formed initially, AND the criteria for a successful or unsuccessful ruck have not been exhibited, then the ruck has not ended.

It would seem that if Kruger's little bit of initial contact was enough to form a ruck, then there was a ruck still when Kemp played the ball with his hands, and the penalty was the correct decision.

A little bit of law alteration could make such a situation clearer.