The one thing that has consistently separated Twitter (NYSE:TWTR) from its competition has been its access to real-time content. Nearly twice the percentage of users on Twitter use the service to follow breaking news compared with the percentage of Facebook (NASDAQ:FB) users, according to a survey from the Pew Research Center.

Source: Facebook.

But Facebook is taking steps to catch up to Twitter in real-time content. Most recently, the company launched "Sports Stadium," a dedicated feed with real-time sports scores, news, and reactions from friends and experts. It's starting with just the NFL, with plans to expand to more sports later. Facebook is also rumored to be experimenting with other topic-based News Feeds, which could be in a similar vein as Sports Stadium. Facebook's push into real-time content is bad news for Twitter, which is already struggling to grow its user base.

A come-from-behind victory?
Twitter certainly has the lead when it comes to sports. Starting in the summer of 2014, the company implemented curated timelines for the FIFA World Cup that drew millions of users to the site throughout the day to find out what was going on in Brazil at the time.

The company followed it up with a similar experience for the NFL every Sunday in the fall. It signed a deal with the NFL to display clips from locker rooms, warm-ups, and games, where Facebook failed to renew a contract after a trial period last season. Now Twitter is  using those clips and others in its curated Moments for sports events, which help users find the most interesting content on Twitter about a specific topic or event.

But there's one thing Facebook has that Twitter doesn't -- 1.55 billion users. It says 650 million of those are sports fans (and it would know), which is more than twice the total user base of Twitter.

Facebook is trying to render Twitter redundant for sports fans -- one of Twitter's biggest audiences. The two companies are currently headed toward a Super Bowl showdown, which will probably give Facebook some valuable data on how to proceed with the feature's expansion to other sports and other parts of the app.

Facebook jumping into real time
Aside from Sports Stadium, Facebook has also been making efforts to increase the amount of up-to-the-minute content on its platform. This summer, it began rolling out live streaming to verified accounts of celebrities and journalists. That feature is now being extended to regular users with a slow rollout that began in December.

Live video streaming on mobile devices is a huge area of interest for Twitter. The company bought Periscope at the beginning of last year before it launched, and helped it grow to over 10 million registered users in a matter of months. Most recently, Twitter integrated live Periscope streams into its flagship product, which will help it compete with Facebook's rollout of live streaming.

Facebook's efforts to become a bigger part of real-time events have cropped up elsewhere as well. Its trending-topics section continues to expand. It's sponsored several political debates for the 2016 presidential election. And it's experimented with live event updates with its Lollapalooza Place Tips last summer.

Twitter is under attack. It's not growing users, and if Facebook's efforts in real-time communication and dissemination take off, Twitter could see its user numbers moving backward as it becomes a redundant product compared with the ubiquitous Facebook. There's a reason the stock price is near an all-time low, and unless it shows it's capable of competing, it might still go lower.  

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.