Ashes: How can Joe Root turn so many 50s into 100s?

Joe Root batted for 225 minutes before being dismissed late on day one

"He still averages 53 in Test cricket and the day will come when he will probably start converting as well as Steve Smith does or the other greats have done. When that happens, it will be scary to see how good he can be and how high his average can jump."

Those are the words of Dawid Malan, who will begin day two of the fifth Ashes Test unbeaten on 55 but without the reassuring presence of his captain, Joe Root, beside him.

And rather than laying the foundations for a potentially match-winning first-innings total, he will instead attempt to guide an out-of-form Moeen Ali and an elongated tail to a respectable score against the new ball and a fired-up Australian pace attack.

England will resume on 233-5 after losing two quick wickets just before the close on day one - the first being Root, caught at square leg, for 83.

So should England be expecting more from Root? Or, as Malan says, should we instead be patient in the assumption he will one day "convert as well as the other greats".

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In Smith's shadow?

Steve Smith averages 151 in this Ashes series

Thursday's innings was the fourth time Root has passed 50 in this series and the fourth time he has failed to reach three figures.

His opposite number Smith has also passed 50 four times but has turned three of those half-centuries into hundreds - two of which were unbeaten and one which was a double (239 to be precise).

Such stark statistics are amplified by the balls faced by each captain in the series. Smith has received 1,258 deliveries in this Ashes series to Root's 604.

"He knows he wants to convert more 50s into 100s," said England coach Paul Farbrace. "It's not something any coach needs to sit him down and say 'do you realise you need to convert more fifties?'"

So why can't Root convert in the same manner as his opposite number? He has converted only five out of 22 fifties since the start of 2016.

"Steve Smith converts fifties into hundreds because he just plays his own way, without risk," former England captain Michael Vaughan told Test Match Special.

"Joe Root gets out between 50 and 100 because he plays unnecessarily risky shots. To become a great player, he needs to realise when the hook or pull is getting him into trouble and shelve them."

Root's fellow Yorkshireman Geoffrey Boycott went one further, saying: "England will always be an up-and-down side until they become a better, more solid batting side.

"You can't win Test matches unless you bat better and put decent totals on the board."

What about Stoneman and Vince?

Root, it should be pointed out, averages 40 in the series - considerably more than two of the three batsman ahead of him in the order.

As England look to plan for two Tests in New Zealand in March, they will surely have concerns over the returns of opener Mark Stoneman and number three James Vince.

Both fell in the 20s on day one in Sydney, and both average in the 20s for the series. Neither man has reached three figures down under.

Hampshire's Vince, in particular, looks susceptible as he continues to get out in a similar manner - 11 of his 19 Test dismissals have been caught by the keeper or the slips.

"I don't think Vince reads a situation well, or the tactics the opposition are throwing at him," said Vaughan.

"I think 95% of Vince's runs come from pure shots so, visually, he looks as good as any England player we've seen.

"But at this level, it's not about looking great, it's about scoring big runs, and he hasn't done that yet."

Mark Stoneman's top score in the series is 56

Surrey left-hander Stoneman was undone by a short ball at the SCG, tamely fencing a Pat Cummins delivery to the keeper.

However, former England batsman Ed Smith believes the left-hander is somebody England should persevere with.

"Stoneman has a big problem with the short ball," said Smith. "His hands almost go up to his eyeline and he has very little control.

"Today's dismissal was one that had been looming. That said, I think there's something there about him that's nice and well suited to opening the batting."