Justin Marshall's Chalkboard: Ryan Crotty v Sonny Bill Williams

Ryan Crotty against Sonny Bill Williams poses an intriguing match-up in Saturday's Super Rugby clash. Photo / Getty

There will be good match-ups all over Waikato Stadium on Saturday night, but the one I want to focus on is the battle between the the No 12s, Sonny Bill Williams and Ryan Crotty. These two might not run into each other that often on the night, but the way they play on attack will have a huge bearing on the fortunes of their respective sides, the Chiefs and Crusaders.

Today I will 1) explain, with the use of this diagram, the similarities between the two, then 2) highlight their different skillsets.

1) Ryan Crotty was outstanding last week against the Highlanders. The Crusaders stepped it up a level from week one and his ability to straighten the lateral movement was one of the main reasons. That's so important, because if you can't hold the drift defenders, then your backline gets squeezed before you make the advantage line, meaning you're starting to play off the back foot.

Crotty and Williams have a similar first instinct when they receive the ball from the inside and that is to step with the outside leg to straighten the attack. We are not talking about a sidestep here. This is simply an initial transfer of weight on the outside foot. This holds the drift defenders and then, if your footwork is quick enough, they can look outside again, or take the contact inside.

The first-five can do this but it is more natural for them and the halfback to drift because it gets them outside the loose forwards. When the first-five straightens, it tends to be straight into the arms of the loosies and there is a limited future in that!
The other option is to bring the blindside wing in.

No second-fives do this straightening of the attack better than Crotty or Williams - though Nonu is close - because they have exceptionally quick footwork. If anything, the under-rated Crotty has the quickest footwork of them all.

2) Where their skills diverge is in the contact area. Crotty is not huge, but he has powerful lower-body strength. So you will see him use his footwork to seek out a defender's weak shoulder and he'll look to break tackles to either bust the line or, at least, break the gain line.

Williams, by contrast, is so tall and strong in his upper body, he is quite happy to go into the contact area very high. You never really see him carry the ball like Julian Savea or Nonu, dropping the shoulder and looking to bump off tacklers. He is confident he can keep his upper body free and that is when he has teammates running off his shoulders looking for offloads.

We all know how dangerous Williams and his phenomenal talent is, but dismiss Crotty at your peril. That's why the All Black coaches and selectors will be drawn to hamilton tomorrow, and why they'll be keeping a close eye on the men wearing 12.