(Arby's recent offbeat image has an unlikely root in the baseball book "Moneyball."Arby's)

In 2016, Arby's had its best year ever.

The fast food chain brought in $3.7 billion in sales, with an average of $1.1 million in sales-per-store in the US — up 20% from 2013.

To put that into context, though: revenues at McDonald's were $24.6 billion in that same time, and its ad spending alone was $734.6 million.

When Paul Brown joined Arby's as its CEO in May 2013, the controlling stakeholders gave him the task of revitalizing a 50-year-old company that had lost relevancy, trailing behind fast-food rivals such as McDonald's.

Brown came to see this gap as a disciplining advantage over its richer rivals, he told Business Insider.

His situation reminded him of one of his favorite management books, one that most people would associate more with baseball history: Michael Lewis's 2003 classic "Moneyball," which was later adapted into an Oscar-nominated film.

"Moneyball" tells the story of how the Oakland A's manager Billy Beane transformed the game of baseball during the team's 2002 season. The team had the third-lowest budget in Major League Baseball, limiting the ability to grow a star-studded team. Beane stretched its budget by building a team based on hard data and research rather than traditional scouting techniques and intuition. The A's became one of the most successful teams in the MLB.

Brown saw Arby's as the Oakland A's, and McDonald's as the wealthy New York Yankees.

( The Pharrell tweet from 2014 became a turning point for finding the brand's voice. Arby's)

"So when you look at it that way, you've got to do things differently," Brown said. "We had to one, come up with a way of talking about ourselves in a voice that actually stood out, but we also had to be more creative about all the channels that you could use to get the message out." In other words, Arby's needed to do more with less.

Around six months into Brown's tenure as CEO, Rob Lynch joined Arby's as its new CMO. One of Lynch's first moves was changing ad agencies, switching to Publicis and agreeing on a comprehensive brand identity that both employees and customers could unite behind.

With the direction of Brown and Lynch, Arby's underwent some "Moneyball" moves:

• Television spots with the cheeky slogan "We have the meats" showcased new and classic menu items, rather than more elaborate vignettes.

• The social media manager was given more freedom. "The light bulb turned on" in January 2014, when he tweeted at the musician Pharrell Williams, who gave his Grammy performance in a large hat that looked similar to the one in Arby's logo. Pharrell responded and the tweet went viral.

• After the success of the Pharrell tweet, Brown and Lynch decided that the Arby's social media presence was going to sound neither too corporate nor like it was trying too hard to be cool. New social media employees ended up creating a brand persona that interacted with fans on a level that felt organic.

• Arby's marketing team decided it wouldn't take itself too seriously. Before Jon Stewart retired from "The Daily Show" in 2015, it responded with an ad highlighting some of his meanest jokes about the fast food chain and told him that they would miss him.

• It targeted niche audiences. The Arby's Facebook team is particularly adept at connecting with the video game community, making obscure, nerdy references that fans engage with. Last year it celebrated deer hunting season with limited-run venison sandwiches in prime deer hunting communities.