As if Wallaby winger Stirling Mortlock doesn't face enough worries tomorrow night when he lines up against All Black giant Jonah Lomu.

Mortlock also has the responsibility of kicking the goals with coach Rod Macqueen increasing the pressure on the eve of the Bledisloe Cup Test by admitting he was worried by the 23-year-old winger's inconsistency.

After finishing the Super 12 season as the series' top scorer, Mortlock was called up to the Wallabies to take the kicking duties for injured fullback Matt Burke but missed all five attempts against Argentina last month.

He then landed 13 out of 20 shots in the second Test against the Pumas and last week's match against South Africa, while also scoring three tries.

"That is a concern going into such a big Test but we've been happy to see that his goalkicking has improved," Macqueen said. "Obviously we've got John (Eales) as a back-up as well.

"It's a fact of life that Burke isn't ready yet. It would have been nice to go into a Test like this with someone whose kicking averages were a little bit better, that's a fact. But he's kicked quite well this week and we have every confidence in him."

Eales has always been a reluctant, albeit expert, goalkicker and immediately sprang to Mortlock's defence when Macqueen suggested he may be called on as back-up.

"You looked at the performance last week of Stirling and against Argentina as well, two very close Test matches, and he put over a lot of crucial kicks at different stages," said Eales, who has kicked 31 conversions and 33 penalties in Tests.

Another huge challenge facing Mortlock at Stadium Australia is the daunting frame of the 119kg Lomu on the opposite wing.

"I've never actually marked him before. He looks like he's returned to form," he said. "In the last match he was involved all the time, they want to get him involved as much as possible and that's what he's doing.

"To match him is going to be big task and I'm looking forward to it, hopefully he doesn't get that big left hand fend going."

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