If you're looking for someone to stand up and take Malceski's role in the team, Laidlaw is the most obvious one given his attributes. It's really a shame for him that he's missing the pre-season games with a knee injury of his own.
It might be Barlow who is the most immediate beneficiary. With Mattner, Tiger and Malceski all fit and firing, one would have spent more time up the ground, on a wing. It is really that position that has come free now, and Barlow has a chance to fill the breach. He'll need to improve in the next few weeks on yesterday's showing but too soon to say he can't.
I don't see any of the rookie listed players seriously challenging for a senior spot soon. Bruce, Terlich and Beckmans are all very raw. The two who didn't play yesterday rawer still.
I really like Smith, and though he didn't get much of the ball yesterday, he did show his exceptionally clean hands. There was one pick up off the ground at speed that showed what he's capable of. He's probably still too slight, though, to make an impact at AFL level yet.
O'Dwyer had a pretty good game but I want to see him back it up. His speed and the odd party trick are not unknown. But he has a tendency to butcher - and I mean truly butcher - about 50% of his possessions. His use of the ball was much better yesterday but he'll need to show sustained improvement in that department before he's AFL ready.
Spot on!

Laidlaw will definitely benefit (providing he can stay fit), and Barlow would probably spend more time on the flanks then on the forward line now that Mattner is likely stay mainly on the HBF. I think Thornton is another that could be given a go, he's a tad undersize as a flanker I guess, but I liked what I saw.
I thought Barlow was probably given too much of a free role today (similar to a role that Goodes had last year) and he seemed to struggle to find where he should be for most of the game. I think we are better off playing him in a more structured role (eg. stay on the flank) and work him into a free-er role once he gets more experience under the belt and start to understand/see where the footy is likely to go.
I fully agree with the assessment of the new rookies - they showed courage and competed, but their skills are extremely raw and right now, not AFL ready at all (and they shouldn't be, I guess).
I'm not as sold on O'Dwyer as most people. Yes, he had a 'flashy' game, he got a lot of possessions and 'looked good' doing so, but he didn't do a lot with his kicks, in fact, I thought his disposals were very poor (though the conditions didn't help). Even the goal he kicked, I thought the kick was fairly dodgy. Right now, I will put Moore, Bird, Jack, Thornton, Laidlaw all in front of him (and in that order) - maybe even O'Keefe and Versprimi (though the latter didn't play).
On another note, I thought Faulks played better than I expected (maybe it's due to the fact that I have close to no expectation for him whatsoever), and he seems more suited as a flanker than a KP.