Meyer, a world track cycling champion, worked hard to get into the only successful breakaway of the 124 kilometre fourth stage from Norwood to Strathalbyn in the Adelaide Hills.
And the 23-year-old's efforts paid off as strong headwinds and a lack of collaboration in the chasing pack conspired to allow the break a clear run to the finish.
Meyer beat Belgian Thomas De Gendt, of Vacansoleil, in a two-up sprint with Dutchman Laurens Ten Dam (Rabobank) in third just ahead of former Australian champion Matt Wilson, also of Garmin-Cervelo.
With the chasing pack arriving 24 seconds later, Meyer took the ochre jersey from overnight leader and compatriot Matthew Goss, who rides for HTC-Columbia.
Ten Dam is now second overall at 10secs adrift, with Goss in third at 12 ahead of Saturday's potentially decisive fifth stage which takes in two ascents of the short but steep Willunga Hill.
"It's just great to get a win for the team," Meyer said. "To get the stage win was the first thing I thought about. Yesterday, I missed the split by seven seconds and lost a little bit on GC (general classification), so I thought, 'It's going to be hard to make that back.'
"To get the stage victory, to throw my hands in the air over the finish line, was just a great feeling."
The four leaders worked well together but with their lead hovering around the minute mark with 30km to go they decided to up the pace.
"We had to really play it cool and wait, the peloton can bring it back whenever they want," added Meyer.
"So we waited until about 20-30km to go and then we really hit the gas, and when we went, we went strong," added Meyer.
Despite the common interest of being able to contend the stage win, Goss's HTC-Highroad team were left almost to their own devices as they fought to defend his overall jersey.
With strong headwinds hindering the chase, HTC's lead-out man Mark Renshaw complained that other teams were simply hanging off their coat tails.
"It's the same old story, we rode all day and we can't be expected to close the gap and ride all day. Some of the other teams need to have a look at themselves," said Renshaw.
"We had one guy from Omega-Pharma and a couple of guys from RadioShack but by then it was too late. With a finish like that, everyone knew it was downhill for the last 10 km."
"It's a little bit disappointing because we lost the jersey."
The race finishes with a 90 km street race in Adelaide on Sunday, and Goss said he would fight all the way -- picking up bonus seconds at the intermediate sprints and at the finish -- to get back into the race lead.
"There are sprint seconds, there's bonus seconds on the line as well tomorrow (Saturday) in Willunga. I will try to take some seconds there and, if need be, the last day in Adelaide," said Goss.
"There's still plenty of opportunities to get the bonus seconds back, but it's just a bit more stress."
© AFP 2011
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