I can personally see both players having good games, as they play quite different styles with Warburton's biggest strengths being his work over the ball and ball carying, and Martyn's main stgregths being his link play with the backs and ability to spot a gap.
In this game, I think Gatland needs to test a few inexperienced players (not too many), and re-introduce a few recently injured players back into the international fold. Therefore I'd go with something like this:
01 Gethin Jenkins (needs gametime to get back up to speed, if he's fit in time that is. Any news?)
02 Richard Hibbard (we all know what Matt Rees gives us. Hibbard has had limited gametime with Wales)
03 Adam Jones
04 Alun-Wyn Jones / Bradley Davies
05 Ryan Jones (see how Ryan goes at second row for Wales)
06 Dan Lydiate
07 Sam Warburton
08 Toby Faletau
09 Dwayne Peel (about time he's given a propper run)
10 Rhys Priestland / Nicky Robinson (Tovey's time will come after the WC)
11 Shane Williams (needs as much gametime as possible imo)
12 Gavin Henson (he must be tested. If he's sh*t, nothing lost, but if he's good, we've gained a quality player)
13 Jon Davies (we need him to make the step-up)
14 George North
15 Lee Halfpenny / Jamie Roberts
16 Matthew Rees
17 Paul James
18 Luke Charteris / Ian Evans
19 Josh Turnbull / Rob McCusker
20 Richie Rees
21 Stephen Jones
22 Jamie Roberts / Lee Halfpenny
I hope Gatland goes for Faletau at 8, as I'd love to see him up against Parisse. I said before that Faletau reminds me of Parisse considering how comfortouble he is both in ball carying and open field running, not to mention his work-rate. I'd then be tempted to give Ryan Jones a propper run-out at second-row to see how he plays in that position at international level. Ryan was back to form in the 6 nations, so he'd be good to have in the team to add some genuine experience alongside that very young backrow. Charteris or Ian Evans could then be brought off the bench.
I'm a little woried again about the options we have behind Adam Jones at tighthead. Craig Mitchell did a stellar job in the 6 nations, but he's gonna be in a race against time to be fit in time for the WC, and even if he is, he'll likely go in with no gametime under his belt. I don't think Scott Andrews is ready yet, as his scrummaging needs a lot of work. One for the future. I'd probably be inclined to use Paul James as backup tighthead and bring another loosehead into the squad (Ryan Bevington or Duncan Jones). I'd probably do that anyway and drop Yapp, even though Yapp was better than I thought in the 6 nations.
In the backs I think a new 10 needs to be tried. The options as I see then are Priestland, Robinson or Tovey. All three are capable, and all three have shown both excellent and not so excellent form this season. Tovey is the form man, but is it too close to the WC to bring another uncapped player into the squad? Is Robinson injured, anyone know for how long? Priestland has been in excellent form for much of the season, but has had a slight dip recently. I honestly don't really mind as long as it's not Biggar!!! I don't think Stephen Jones should start either. He's still our no. 1 ten, but we know exaclty what he offers, so now's the time to see who else can step-up for us. Peel should be given a propper chance at 9 to proove he's the man to re-ignite this Welsh backline by showing Gatland that a pondorous 9 like Phillips stiflies everything before it's even allowed to get going.
I see Gavin Henson as a must for this game. He needs to be tested, simply because the risks are worth it. If he performs, we've suddenly got a very good player back, who offer's an all-round game none of our other centres do at the moment. Davies probably comes closest, but he's failed to convert his regional form to the international stage thus far. For that reason, I'd also start Davies alongside him at 13, to see if he can finally make that step-up. Davies is also a prooven finisher who could thrive feeding off Henson inside of him, putting him into space.
I'd be tempted to play Shane on the wing. We need him in top form for the WC, and considering his recent injury lay-off that might mean giving him plenty of gametime pror to the competition. However if Gatland decided wrapping him in cotton wool is the way to go, I'd have no problem with that and giving Brew another shot on the wing with North on the other. Who do we play at fullback in Byrnes absense? I'd go with Halfpenny or Roberts personally. If Jones doesn't start at 10, we're probably going to need Halfpenny on the pitch to kick to the posts (although that's not hugely important in a BaaBaa's game). However I still think Roberts could be a great attacking weapon from deep, allowing him to choose where to enter the attacking line, and picking clever angles from deep. As others have said, there's always Priestland, Tovey and Fussell as options there aswell. I'm kinda glad Byrne is injured for this game, as Gatland is now forced to find a propper replacement instead of simply shifting Hook back to 15.
