After England's 69-3 win against Tonga, head coach Eddie Jones has a real selection quandary for the next game against Australia on Saturday.

England's captain was forced to withdraw from the starting XV after a positive Covid-19 test on Friday.

George Furbank stepped in at 10, with Marcus Smith coming off the bench and scoring a late crowd-pleasing try.

Because he only came on for the last 28 minutes, we have not learned too much about Smith.

But we did see that he looks just as comfortable playing for England in front of a packed Twickenham crowd as he does playing for Harlequins.

There were some tired Tongan legs out there when he came on, and because Smith is so sharp in his mind and his body at the moment, any half gap and he is gone.

How can we possibly doubt him? He has not given us any reason to say he is not going to perform at that level. So I would like to see Smith start against Australia and South Africa.

'No better chance to see what Smith can do'

Admittedly it will be difficult for Smith going into an enormous Test match against Australia when he has not started one of those before.

We do not know what his leg niggle was during the week, but the 22-year-old could not get his training in because of it.

I am sure he will get to train this week, but he is going into slightly uncharted waters with that.

But if Ben Youngs and Manu Tuilagi play the way they did against Tonga, it will be a big help having those two around him.

Are we going to get a better chance to see what Smith can do than at home against Australia, where you are going to have to unlock them?

If you go through the motions against Australia, you are going to get unpicked. They proved in the Rugby Championship, where they twice beat South Africa, that they are not the team of three or four years ago.

Looking at the video of Saturday's game, the Wallabies are going to have to look at Tuilagi, Henry Slade, Adam Radwan and Jonny May. They have got a lot to think about.

All of a sudden, if you put Smith in there, they have to pay attention and spend a lot of their week studying what England can do.

They are never going to cover everything, but it is going to create a lot of indecision.

Whereas I just feel with Farrell at 10, it slightly makes Australia's defence easier. He is naturally not as threatening as Smith.

England's attacking intent

England had much more attacking intent against Tonga and it was noticeable.

It is going to seem biased as a past scrum-half, but if you want to input pace into the game, the scrum-half is going to be the barometer.

Youngs had intent to play with pace - quick-tap penalties, line-outs, quirky little nips round the short side for his try with Jamie George.

The amount of times I have watched Youngs play and he has threatened to take a quick tap penalty and everyone else has said no.

Now he probably has more people around him who want to do that too, and when England had real intensity, breaking the opposition up, they looked like a really dangerous side.

Cause for optimism

I thought England's senior players in particular played well.

After Jones' shake-up this autumn, with the likes of fly-half George Ford left out, they have obviously realised they are nowhere near guaranteed selection for the World Cup in two years.

I thought Courtney Lawes had a real skipper's presence as he captained in Farrell's absence, and Maro Itoje and Jamie George were outstanding. Youngs stepped up, maybe because Farrell was not there.

To win by such a large margin happens with strategy. It is not going to come with just flinging the ball round and having loads of youth and enthusiasm.

It was a very accurate display and that meant the game opened up for the last 20 minutes, giving someone like Smith the space to run amok.

To be the best team in the world, you have to have razzle-dazzle across your whole backline.

I maybe would have liked to have seen a bit more of wing Radwan. You could see Jonny May had noticed everyone was talking about the 23-year-old and did not want people to forget about him.

He was on and off his wing, making breaks, passing and kicking. He was everywhere.

Radwan had a couple of breaks and showed some real gas, but otherwise you could tell it was the biggest game he has played so far and that is understandable.

Contrary to that, Freddie Steward at the back looked like he had already got 40 caps for England.

He was reading the game, his error count was low and he was assured fielding and kicking the ball. It was really impressive.

Overall, it was a good all-round performance considering the coronavirus disruptions to their preparations and I am optimistic going into the Australia and South Africa games.

Matt Dawson was speaking to BBC Sport's Becky Grey.