Shane Watson and Chris Rogers have been confirmed as Australia's openers for the opening Ashes Test, which gets underway at Trent Bridge a week on Wednesday.
Lehmann had already hinted that Watson, who opened at times in the last two Ashes series but has batted lower down in the line-up of late, will return to the top of the order.
And he has now revealed that Watson will be partnered by the 35-year-old Rogers, who has played just one Test before, against India back in 2008.
Regular opener David Warner was banned until the first Test after punching Joe Root of England in a Birmingham bar last month and today's announcement makes it less likely he will be recalled immediately.
Cricket Australia tweeted on Monday afternoon: "Darren Lehmann confirms Shane Watson and Chris Rogers will open the batting for Australia in the first Ashes Test at Trent Bridge."
Watson and Rogers will both be in the side for Australia's final warm-up match against Worcestershire, which starts on Tuesday.
Ed Cowan, who had been first-choice opener under Arthur, looks set to bat at three this week but may now find it hard to force his way into the Test line-up.
Rogers, who has scored 790 runs in 15 innings for Middlesex this season, said: "I'm looking forward to it and, if I do well, I can be particularly satisfied.
"I have nothing to lose and, as a group, we are very hopeful.
"You can't write off an Australian side, we saw that against the Lions the other day. Hopefully, we can shock a few people as well."
His age does not bother Lehmann, who added: "You can always improve, whatever age you are.
"That's what we want to do, learn and get better, and if we can keep doing that on and off the ground we'll be fine."
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