At 15, Alaba was already involved with Austria Vienna's first team, then at 17 he became Austria's youngest ever capped player.
Now, after a superb Champions League campaign, Alaba is attracting the interest of Europe's biggest clubs, but with the approach of a veteran, the teen isn't allowing the speculation to faze him.
"I know nothing about it and won't let it drive me crazy," he smiled with reporters when asked about the United and Barca rumours. "I will give my best in every practice, learn and develop myself further.
"It's nice to know people have noticed you. But you also need to realise that this is part of the job I'm in. I'm trying to deal with it normally."
Spotted by Bayern as a 15 year-old, Alaba had played barely five reserve-team games for Austria Vienna before he was snapped up by the German giants. He was immediately playing regular first team football for Bayern II in the Third Division and his progress never faltered, as he won his first cap that season before being promoted to the senior team the following campaign.
"Everything has gone so fast," he reflected recently. "In my development as a player, in my development as a human being. I am, for example, more confident on and off the pitch. The time since I first came to Bayern has really gone fast, it's crazy."
This past season, BILD named Alaba as Bayern's best - ahead of the likes of Franck Ribery and Arjen Robben.
"Of course it's an honour. I'm just grateful for the support of the coaching staff and my teammates. Especially Franck Ribery, who has been very important to me - even if he doesn't like to track back!"
While still regarded as a junior member inside Bayern's star-studded locker room, for country Alaba is already a leader - and admits he enjoys the responsibility.
Austria coach Marcel Koller is playing Alaba in central midfield and the youngster says he's loving the role.
"I know I can play better for the team not as a wing-back, but in the midfield. I am pleased. I believe in myself, in any case, because in this position, I just feel most comfortable."
But it could've been so different if the Nigerian FA, usually so diligent with players who qualify for the Super Eagles, had been on their game regarding Alaba. Born in Vienna to a Nigerian father and Filipino mother, Alaba admits the NFA never were in touch when he was first considering his international options.
"There was a request from the Philippines (to play for them), but Nigeria has never approached me. And Germany would anyway never been an issue, since I have no connection to the country," he revealed.
"My Mum is from the Philippines, my Dad from Nigeria. I've visited both countries, most recently Nigeria."
His strong family background and maturity on the pitch for club and country now has convinced Barcelona sports director Andoni Zubizarreta and Manchester United manager Sir Alex Ferguson to take a closer look.
Ferguson made a personal check on Alaba during the German Cup final this month, while Barca's interest had Dad George knocking on Bayern's door wanting to know where his son stood in their long-term plans.
Bayern have made it clear, however, that the youngster is not for sale, with football chief Christian Nerlinger declaring: "I would like to extend Alaba's contract by 15 years!"
With his current deal running to 2015, Bayern can afford to be calm.
And even if he were to quit Bayern, United and Barca may be overlooked for a third option, as Alaba revealed when first breaking into the Bayern first team: "I always set myself little goals that I want to achieve step by step. My next goal is to prevail and one day play in the first team (of Bayern Munich). Then I want to go to England, preferably to Arsenal."
Given his rapid rise so far, few would bet against David Alaba reaching his "little" Premier League goal - sooner rather than later.