Forget cash. On Tuesday, McDonald's hamburger fans were able to withdraw a Big Mac from an ATM.

Big Mac lovers who visited a McDonald's eatery in Boston's Kenmore Square were able to bypass the counter and instead head straight to an automated teller machine that dispensed two new versions of the signature sandwich, along with the original. All were free.

The unique promotion was intended to spotlight on McDonald's new single-patty Mac Jr., and the Grand Mac with plus-sized patties. The sandwiches, which will be on menus for a limited time, were available through the ATM just in time for the lunch rush.

Beyond highlighting new variations of the Big Mac, the McDonald's ATM that debuted in Boston also focused attention on the role automation might play in food service going forward.

Vincent Spadea, McDonald’s owner and operator in the Boston region, downplayed the idea that the ATM signals a new direction for the restaurant chain.

"This was purely a fun, one-day activation to generate excitement around the new Big Mac options,'' he said. "This is not a move towards automation. However, we are always looking to implement advanced technologies and how we can modernize our restaurants in an effort to better serve our customers."

For its part, McDonald's used the occasion to promote its iconic burger.

“McDonald’s listened to their customers who asked for different ways to enjoy the one-of-a-kind Big Mac taste at the size that best fits their appetite,’’ the restaurant chain said in a statement.

The fast food giant has made much of its efforts to revamp its menu. It has made breakfast foods available all day, and is now temporarily tweaking the classic Big Mac at least when it comes to size, not components. Last week, in another promotion of the sandwich's new larger and smaller sizes. McDonald's gave away 10,000 bottles of the Big Mac special sauce

But McDonald’s may need to be even more inventive to boost sales.

"Menu tweaks are very important in creating a sense of newness and bringing in more customers,'' says Neil Saunders, managing director of the retail analysis firm GlobalData. "However, it is unlikely that new smaller and larger versions of the Big Mac will succeed in this as they are simply variations of a product that already exists. McDonald’s really needs to think beyond its core menu and introduce more innovative products, even if they are for a limited time only."

Saunders says that with wages and other costs on the rise, streamlining operations is essential, and automation is likely to play a role.

"Automation is almost certain to be a key strategy in McDonald’s playbook,'' he says. "Automation may take the form of more self-ordering via touchscreens in store or eventually via mobile devices. Or it may be something more radical like robots cooking product. Automation will also allow McDonald’s to increase menu selection without hiring more labor to cope with all the variations.''

McDonald's reported net income of $1.19 billion during the final quarter of 2016, a 1% dip from that period the previous year. The slight downturn sparked concerns that its popular all-day breakfast offering has begun to lose some of its luster.

CEO Steve Easterbrook said during a call with investors earlier this month that home delivery might be a way to boost growth, and the chain is in the preliminary stages of testing it in Florida.