Jamie Roberts: Wales have to build on fightback to worry the Wallabies

Millennium Eye: The second half against the All Blacks is the best we have played this autumn

The running of Australia’s No 10 Kurtley Beale will be a big threat to Wales this afternoon (Getty Images)

Frustration. It is the only word that sums up the last three weeks, both personally and for the team. I was completely gutted on Saturday. I only lasted 20 minutes against Argentina before getting knocked out cold. In the Samoa game I didn't see too much of the ball and was pretty disappointed, so to last 20 minutes against the All Blacks last Saturday was just a nightmare. It was one of those knocks that was completely disabling. There was no choice but to come off. Utter frustration.

We have one last chance to put things right this afternoon and bring a happy end to what has been a tough autumn. I'm ready to go – I ran for the first time on Thursday and passed a fitness test. I may hurt this afternoon – that is kind of inevitable after such an intense period – but I will be out there.

If anything, the autumn series is tougher than the Six Nations. There are breaks in the Six Nations, but playing four on the bounce is hard, especially against four big, physical sides like Argentina, Samoa, New Zealand and Australia. But then there is no substitute for playing for your country. That is something you can never get tired of no matter what your body might be telling you and I promise you we are well up for it this afternoon.

The second half against the All Blacks is the best we have played so far this autumn. We have to carry that into this afternoon and reproduce it over 80 minutes. The first half was disappointing but the second half was spot on – that is where we want to be. We lost but there are positives.

Overall the key thing about that second half against New Zealand was the dynamism on the gainline – our carriers went forward, put us on the front foot and all of a sudden we can play rugby. It is a game that has to be played on the front foot. You need people running hard, getting over the gainline. That is what we failed to do in the first two-and-a-half games, we have not taken that physical battle to the opposition, certainly in attack. At last in the second half we did – suddenly they were on the back foot. It is harder to defend then. We have to take it to Australia, get over that line. That needs to be the mantra: get over the gainline.

Australia are different again to the three sides we have already faced. They are capable of producing some breathtaking attacking rugby. If you give them space and let them play they will trouble any team. They are talented footballers and Kurtley Beale at 10 is a big threat. He runs well and is adept at creating space for those inside him. We need to impose ourselves, starting with the set-piece, keep the ball through phases and get on that front foot. If we can do that then we will create problems for them.

It is so important in a series of games like this to take each one as it comes. Yes I know that is a sporting cliché but you cannot afford to carry baggage. It is crucial to have that mindset, and maintain it even when you get into the game itself. The ability to move on from making a mistake during a match or a poor performance as a whole is an important part of a player's make-up. Players deal with that in different ways. I am quite logical in my thought process and like to work out problems myself – answering my own questions.

I am fortunate that I have my medical studies as an exit from rugby. It is how I get away from the scrutiny that comes with the game. I escape to the library or a lecture hall and lose myself in something unconnected with rugby, although in a few weeks' time I might be saying something different. The next nine weeks are pretty much hell for me. Every spare minute of the day in between rugby I will be revising for my finals in March. I have worked out a programme that takes me through to the Six Nations. As of Monday morning the nine-week plan of attack begins.

But first Australia. We are two sides that know each other well – we may have lost the three Tests in Australia in the summer but they were all close- run games. It is now four years since we beat them and that's a win I like to take credit for – my collision with Stirling Mortlock early on cost them their captain (and me a fractured skull)!

I would prefer to stay on the pitch for 80 minutes this time – and enjoy a win at the end of it.

All-in line-out try was a success, but will it catch on?

At the highest level there are times when you have to think outside the box and in Warren Gatland we have a coach who keeps showing he can do just that. Take that try from the all-in line-out against the All Blacks last weekend when Scott Williams went over in the middle of a red tide. Warren has done that move with a few teams in the past but that is the first time we have used it – he brought it up in training in the week and it worked a treat on the day.

It's a great tactic, pretty innovative – if you win the lineout it's impossible to stop the try really because there are so many numbers there. But you have to make sure you win the line-out! Otherwise it's a frantic 100m foot race back towards your own line. I wonder how many other teams we will see try and use it now.