Rogers, 38, and Dalhausser, 32, showed they are still a force to be reckoned with as they wowed an enthralled crowd of neophyte Londoners with speedy spikes and impassable blocks, overpowering Kentaro Asahi and Katsuhiro Shiratori in two sets.
"There was no pressure coming in here really. We talked it out a lot over the last three weeks, hey let's have fun, because we didn't have fun that first week in Beijing, it was nerve-wracking," Rogers told reporters.
"Now we're mature. We're not little kids anymore," he said with a smile.
Beach volleyball matches are scored using a best-of-three-sets system in which the first two sets are played to 21 points and the third, if required, goes to 15 points. A two-point advantage is needed to win a set.
Rogers and Dalhausser won 2-0 (21-15, 21-16) in front of a boisterous crowd in the 15,000-seater stadium built for the event on Horse Guards Parade, right next to Prime Minister David Cameron's Number 10 Downing Street residence.
The London crowds have been loving the beach volleyball, a sport not often seen in rainy Britain, not only for the action on the court but also for the pounding music, raunchy dance routines and exuberant commentary that come with the sport.
After a day of heavy downpours, the rain finally stopped during the night-time session to the delight of spectators who cheered at the top of their voices, stomped their feet and did one Mexican wave after another.
"The atmosphere in there is intense. And it's a beautiful venue," said Rogers.
At the London Games, 24 pairs of each gender are divided into six pools for the first phase, which lasts until August 2. The competition then moves to a knockout stage.
Earlier on Sunday, Emanuel Rego and Alison Cerutti of Brazil, the main rivals to Rogers and Dalhausser in the race for gold, fought back from a set down to win a surprisingly tight match against a low-ranked Austrian pair.
Emanuel and Alison took an hour to subdue Clemens Doppler and Alexander Horst, who saved three match points as they frustrated the Brazilians with one dramatic block after another.
The favourites eventually prevailed in their first game, winning 2-1 (19-21, 21-17, 16-14).
"They knew very well how we played, but we did not know them. So we had to find their weaknesses first to beat them," Alison told reporters after a match that started under bright sunshine before a heavy downpour in the second set.
"I did not even know it was raining. I did not see anything. I was just focused on the game," said Emanuel.
The Brazilians are an unusual pair in that Emanuel, 39, had a long and very successful career with former team-mate Ricardo Costa Santos, winning Olympic gold in Athens in 2004 and bronze in Beijing in 2008, before pairing up with Alison, 27.
Ricardo is also competing in London with his own new team mate, Pedro Henrique Cunha.