The six biggest storylines to follow in the 2016 MLS season

Last year, Major League Soccer expanded to 20 teams and signed several of the biggest stars to have ever plied their trades in American soccer. This time around, there are no new expansion teams or blockbuster signings, but there are still plenty of plotlines to follow as MLS kicks off its 21st season.

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1. Will Jordan Morris’ move to Seattle pay off?

It wasn’t quite on the level of LeBron James’ "The Decision," but Morris’ decision to spurn Bundesliga side Werder Bremen and turn pro with the Seattle Sounders may have been the most watched move by a young player in American soccer history.

At the time, there was disappointment over Morris, who scored his first senior U.S. men's national team goal in a friendly against Mexico last year, choosing MLS over a chance to test his mettle in one of Europe’s big leagues. But now, with striker Obafemi Martins having departed Seattle for China, Morris could feature prominently in Sounders coach Sigi Schmid’s plans. And with playing in Seattle affording Morris the opportunity to partner with Clint Dempsey, spurning Bremen for MLS may not turn out to be a bad move for American soccer’s latest promising young prospect.

2. With a preseason behind them, will last season’s big Designated Player signings come good?

Last season, we saw MLS make several of the biggest signings in its history. But unlike David Villa and Kaka, who joined in the offseason, Steven Gerrard, Frank Lampard and Andrea Pirlo all joined the league in midseason after grueling European campaigns. As a result, none of the three had the kind of season fans were hoping for.

"It’s a huge thing for me now to have a preseason,” Lampard told Yahoo Sports during MLS Media Day in January. "I’m sure Andrea [Pirlo] will say the same. It’s not easy coming in halfway through.”

“I think the good thing is we got a preseason to work stuff out,” Gerrard told Yahoo Sports. “We’ve got a preseason to get used to each other. You know I come halfway through last season, no one in the dressing room knew me, my character, the way I played, my movement. I didn’t know nothing about them.”

Say it again: preseason. We shall see.

3. Can the Galaxy’s stars align?

There were lots of big signings and big departures for the Los Angeles Galaxy in the offseason. Mainstays of the side that won three MLS Cups in four years, Omar Gonzalez and Juninho, were sold to Liga MX sides. Meanwhile, a trio of "experienced" European veterans arrived to join a team that already has a number of key players on the wrong side of 30.

With the likes of Gerrard, Robbie Keane, Ashley Cole, Nigel de Jong, Jelle Van Damme, and Giovani Dos Santos, the Galaxy has one of the most star-studded squads MLS has ever seen. It’s also one of the oldest.

For Galaxy coach Bruce Arena, the key will be finding a balance between the quality and experience of his aging superstars and still-developing talents like Gyasi Zardes and Sebastian Lletget.

Much of the onus could fall on Dos Santos. At 26, the Mexico playmaker is still in his prime and has the talent to be as good as last season’s league MVP, Toronto FC’s Sebastian Giovinco. If Dos Santos finds his feet and Arena gets the balance right, the Galaxy could be the team to beat once again.

4. Can lightning strike twice for Portland?

Portland Timbers coach Caleb Porter seemed to take a page out of Bruce Arena’s playbook last season, igniting his team into a winning streak just when it mattered and riding that momentum into the MLS Cup final. The good news for Timbers fans is that the team that won last season’s MLS Cup is still largely intact.

Despite losing key defenders like Jorge Villafana and Rodney Wallace, Portland’s attack remains one of the strongest in the league. Argentine DP Lucas Melano and Colombian winger Dairon Asprilla are still there to provide danger from wide areas, while Jack McInery has been brought in to provide support for Nigerian target man Fanendo Adi.

But the real question for Timbers fans is whether Darlington Nagbe will be able to pick up where he left off last season. If so, Portland may put to rest any lingering suspicions that last season was a fluke.

5. What does the Tim Howard signing mean for MLS?

It’s all but confirmed that U.S. men's national team goalkeeper Tim Howard will leave Everton to join the Colorado Rapids this summer. Howard reportedly will exit Goodison Park for a transfer fee of between $600,000 and $750,000. His contract, which will run through 2019, will see him receive an annual salary of $2 million.

That will make Howard the best-paid goalkeeper in the league. And while 36 isn’t terribly old for a keeper (Gianluigi Buffon is 38), splashing that kind of cash and giving up a DP spot to a keeper, who by most indications is past his best, doesn’t do MLS any favors in terms of shaking it’s retirement league reputation.

6. Is Vieira the man to lead NYCFC?

Although he’s relatively inexperienced managerially speaking, first-year New York City FC head coach Patrick Vieira has an undeniable pedigree in the game. But as we saw with Filippo Inzaghi at AC Milan, a legendary player coming off a successful spell coaching the youth squad doesn’t always translate into success with a senior team.

With salary caps, rosters and the challenges of putting together a balanced side when you can’t just go out and buy the players you need, the Frenchman has admitted "that coaching in the MLS is of course harder than in Europe." Harder still when you’re at the helm of a team that plays its home matches on a reconfigured baseball diamond and is anchored by a midfield duo with a combined age of 73.