Rees and fellow Welshman Adam Jones were credited with strengthening the Lions' scrum against the Springboks and the 31-year-old headed home with his reputation greatly enhanced.
A squad place for the trip to Australia next summer looked highly likely immediately after the 2009 tour but a series of injury setbacks has blighted his progress in recent months.
A neck problem saw Rees miss out on the 2011 World Cup campaign at a time when he was national captain, while calf damage ruled him out of three of his country's fixtures in their 2012 Grand Slam winning season.
Rees travelled Down Under for Wales' three-Test series with the Wallabies as reserve hooker but finished the tour as first-choice and now he is aiming for an injury-free year and a chance to return to Oz with Britain and Ireland's elite.
"It's going to be interesting and, for me, that's the end goal, the Lions," Rees told Wales Online.
"There may be a Lions tour at the end of next season, but I have to take it a game at a time.
"My form (last season) was pretty frustrating. It was just a case of getting through the season after having the neck operation then missing the opening of the Six Nations because of a calf injury.
"I was playing catch-up all season. Missing pre-season training, because of my neck, didn't help me.
"I came back and was playing more or less straight-away because the season was well underway.
"The main aim was to play but the injuries and missing the World Cup knocked me down a few pegs.
"But I am confident, if I have a good pre-season, I can get back to my best."
First Rees has to ensure he is number one with his region as the Scarlets target success under new head coach, and former Lions tourist, Simon Easterby.
Wales colleague Ken Owens and U20s captain Kirby Myhill are among the men challenging for the Scarlets jersey but Rees is convinced he can make the No2 shirt his own again if he can stay injury free.
"I have got a lot on my hands with Ken, Emyr and Kirby," added Rees, who believes the time has come for a Scarlets side featuring the likes of George North, Rhys Priestland and Jon Davies to deliver some silverware.
"I know I am capable of nailing down the No.2 spot. The playing field wasn't level last season because I was playing catch-up.
"Our back-line is probably one of the best in the RaboDirect Pro12, if not Europe, and the big challenge for us, as a pack, is to get them good ball.
"It's been frustrating for us the last few seasons. For a number of years we have used the term development as a way out for not winning silverware.
"As much as the players and staff here need some silverware, we want to bring some success for our supporters. They deserve it because they're great."