Leedham said: "It was a good first game for us to play Australia. They are a good team and it was good to get our feet wet against such a high quality opponent.
"We had a good first quarter, but the second wasn't so great but it's a lesson for us to learn. When we make mistakes, they punish us and that's what they did," Leedham added.
Australia played like an experienced Olympic nation, GB meanwhile have got their first game nerves out of the way and GB coach Tom Maher was happy about that along with his team's showing: "It was a really good performance from us.
"I am happy that we are here in the Olympics, all our players are first time Olympians and on their debut they played the number two team in the world. I hope the girls enjoyed it."
With a passionate home crowd behind them, emotions were running high to begin the game and Australia's main threat Liz Cambage scored first, while also drawing a foul on Stef Collins.
GB attacked 6'8" Cambage early and the plan worked as she would sit on the bench for the remainder of the first period on two early fouls. Natalie Stafford connected from mid-range and a bucket from Leedham gave GB a 7-6 lead as the crowd at the Olympic Basketball Arena roared them on.
The Aussies hit back, and led 11-7 on the back of a fluke three-pointer from Jenna O'Hea. Seattle Storm forward Lauren Jackson scored the last five points of the first to give Australia a 16-11 lead after the first.
GB were held scoreless for the first five minutes of the second period as Australia would continue their scoring which peaked at an 18-0 run before Julie Page connected on a tough lay-up.
The hosts showed promise, attacking the medal hopefuls as Cambage picked up her third foul for the Aussies, but unfortunately for GB, Jackson was in sublime form and connected on a long-range two-pointer to give Australia a 35-19 lead as she hit 15 first-half points.
Team GB stepped up their offensive credentials, with Azania Stewart and Julie Page connecting to trim the gap to 35-23, as the crowd chanted for Tom Maher's side.
Suzy Batkovic hit for Australia which was replied to with a three from Chantelle Handy as the teams went into the half with Australia up 37-26.
Batkovic opened the third quarter as Australia took 43-28 lead early thanks to a jumper from Jackson. GB quickened the tempo of the contest, and scored two quick fast-break points to force Aussie coach Carrie Graf to call a timeout. Great Britain pulled it back to 45-34 with four minutes of the third played.
GB upped the tempo of the game once more and attacked Jackson to good effect as Australia's number 15 sat down due to foul trouble. A bucket from Page reduced the gap to 51-40 and the decibel levels rose again inside the Basketball Arena.
Australia though responded, and ended the third with a 6-2 run to lead 57-42 going into the fourth.
O'Hea got the final period started with a three-point play as the Aussies looked to put the game fully out of GB's reach. But the hosts fought back with a three from Rachael Vanderwal and buckets from Stewart reducing the gap to 66-53.
Australia though never let their double-digit lead slip to clinch the win in their Olympic opener.
Despite defeat, Stewart, who hit eight points, was upbeat: "It was a great start for us obviously playing Australia was going to be a tough game but we're just getting our feet wet," she said.
Australia were led by Jackson, who hit a game high 18 points.
Team GB women next play Canada on Monday night, tip-off at 8pm. The GB men play Russia tomorrow in their opening game of the London 2012 Olympic Games.
