MLS and Twitter are teaming up to add some bells and whistles for the league's first Decision Day–simultaneous season finales.

This Sunday, on the final day of the MLS regular season, the U.S. soccer league is borrowing a dynamite concept from the English Premier League: Simultaneous season finales. Every team from the Eastern Conference will have its games kick off at 5 p.m. ET, and every team from the Western Conference will have its games kick off at 7 p.m. ET.

MLS is calling it Decision Day, and there will be plenty at stake, from the Supporters' Shield for the league’s best regular-season team (with the New York Red Bulls and FC Dallas fighting for the trophy) to jockeying for playoff position (teams that finish first and second in each conference will avoid a mid-week single-game playoff) to getting a spot in the postseason.

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As of Tuesday, there were still three playoff spots up for grabs in the West (with four teams vying for them) and one in the East (down to New England and Orlando City).

To make Decision Day even bigger, MLS is expanding its partnership with Twitter to do some interesting, interactive things, including:

• Sharing Vines of goals, plays and moments during the four hours of game play.

• Sending Twitter mirrors to all 20 MLS teams to provide behind-the-scenes content all week. For example, from MLS All-Star 2015:

• Sending a social media content creator to all 10 game-day markets to show what’s going on on Twitter, Vine and Periscope.

• Incorporating user-generated content from the sites of the 10 games.

• ​MLS will also give away a trip for two to MLS Cup for fans who submit their photos or videos via Twitter using the hashtag #DecisionDay.

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It’s fair to assume that Decision Day (and the #DecisionDay hashtag) will appear on the new Twitter Moments function as well.

“There are a couple things we’re doing,” said Danny Keens, Twitter’s head of North American sports partnerships. “One is in-game match highlights, which we publish on the platform in real-time as events are unfolding. And there a bunch of content initiatives we’re doing at venues. For fans, we’re able to drop them into multiple MLS Decision Day games at once. So fans can connect with all the action that’s taking place on the day and bring them closer to the action than ever before, with Twitter being the center of that universe.”

Howard Handler, MLS’s chief marketing officer, let out a knowing laugh when asked if it was difficult to organize the logistics for two sets of five games each kicking off at the exact same time at such a busy time in the U.S. sports calendar.

“It definitely was,” he said. “Because we always have to deal with stadium availability issues. It’s a competitive time of year for a handful of our stadiums with football and baseball going on. It was an unusual idea, but I think the TV networks were like, ‘O.K., this is some schedule innovation. We like that.’ It creates a sense of urgency, and it allows us to do some creative things.”