This SAP president has a fabulous career because he spent one sad and lonely holiday at work

About a year ago, Alex Atzberger, 39, was promoted to president of SAP Ariba, a procurement cloud service that SAP bought for $4.3 billion in 2012.

It was a shining moment in one of the most amazing career stories we've ever heard.

He started by dissing SAP to Clay Christensen

While Atzberger was in grad school at Harvard in 2005, he took a class from Clay Christensen (the famous author of "The Innovator's Dilemma"). He wrote a paper that argued that a tiny, little-known company at the time called Salesforce.com, was going to eat SAP's lunch. He said that Salesforce was focusing in an area that SAP was overlooking at the time, cloud computing (although it wasn't called cloud computing back then).

"That paper got me to SAP," Atzberger tells Business Insider.

Christensen, who knew SAP's co-CEO at the time, Jim Hagemann Snabe, was impressed enough to give the paper to Hagemann. And Hagemann was intrigued enough that SAP recruiters soon started calling him.

At first, Atzberger wasn't interested in a job at SAP. He wanted to go to a startup.

But he changed his mind when he realized that the "bigger challenge" was getting access to SAP's 250,000 customers and "moving them forward," he says.

So he took an entry-level position in SAP's business analysis department, and began toiling away in relative obscurity, crafting plans to move SAP into new markets.

On July 4, 2007, everything changed for him.

While Atzberger's coworkers were all out at BBQ's and beach parties for the 4th of July, he was working in the empty office. Not born in the US, he had no family to hang with.

He wasn't completely alone. Bill McDermott was also there. McDermott, who had joined the company a few years earlier to run its US operations, had recently been appointed to SAP's Executive Board. (SAP is ruled via an oligarchy, by its all-powerful Executive Board.)

McDermott was roaming around the empty office "looking for someone to help him with a PowerPoint presentation." McDermott wanted to tell the board "the story of how we are going to turn sales around," Atzberger remembers.

McDermott spied Atzberger and roped him in to helping. Atzberger spent the whole holiday weekend doing this presentation for the boss. When he finished, he thought he'd never hear from McDermott again.

But after McDermott gave the presentation, he called Atzberger on the phone, thrilled. "Alex, I want all my future presentations to the board be done by you," he said.

"He didn't care who I was working for, or what my job was at the time," Atzberger laughs.

So this junior business analyst, filled with strategy ideas, now had a direct access to one of the most powerful men in the company.

Naturally, Atzberger's career took off after that. He went to Japan and China, helping SAP grow in those markets, eventually becoming a senior VP in China.

That's when McDermott called again

"I was in Shanghai boarding a flight when Bill called me up and he asked me to become his chief of staff," he says. Again, he almost didn't do it. It sounded like a staff role when he aspired to run a business unit.

But, it's hard to say no to McDermott, so he took the job and "it was really good," he says. He learned a lot about running a company while he traveled the world with McDermott, who had become sole CEO by then.

"Then we did the acquisition of Concur," Atzberger remembers. SAP bought Concur, a cloud expense management company, for $8.3 billion in December 2014.

During the process, Atzberger got to know Concur Technologies CEO Steve Singh.

The three men were taking a long international flight together discussing plans to integrate Concur into the company.

Atzberger was asked his thoughts about the strategy and about his career goals. He thought he was about to be offered a right-hand-man job with Singh at Concur, like a COO job, to give Singh a SAP insider.

Instead, McDermott offered him the top spot at Ariba. Ariba's top executives had left SAP a few months earlier.

Aspiration achieved. He was now running his own multi-million business unit. (SAP doesn't report Ariba's revenues, but says it is growing. It was generating about $444 million in 2011.)

And all because a young Alex Atzberger spent a lonely holiday weekend working.

"I was fairly lucky," he says.