Now that we're certain that Minnesota is moving to Major League Soccer next season, fans can start in on the hardest part of following an MLS team: trying to learn the roster rules, which are both long-winded and written in incomprehensible legalese. Understanding them, never mind simplifying them, is nearly impossible. The league itself is of no help, especially given its habit of refusing to release even the most basic information about rosters, trades, or other details.

To give you a complete summary would be impossible, but there are a few important rules. Like the NHL or NBA, the league has a salary cap. This year, that cap is set at $3.66 million, but every team can sign three "designated players," whose salaries beyond the maximum salary ($457,500) don't count. This is how a team like New York City FC can spend a combined $16.2 million on Frank Lampard, Andrea Pirlo and David Villa. When a big-deal foreign player comes into the league, it's almost always as a designated player.

Rosters contain between 18 and 20 players, with an additional eight men on supplemental and reserve rosters, similar to NFL taxi squads. Each team can have up to eight non-domestic players, and while those spots can be traded to other teams, every team is mostly made up of players from the United States and Canada.

Young American players have a fairly familiar path into the league, with one exception. If a player gets his start with a team's youth academy, the team has priority to sign him — the "Homegrown Player" rule, which is in place to encourage teams to develop youth players. Otherwise, college or youth players usually will enter the league through the MLS SuperDraft, which is just like college drafts in other pro sports.

For older players, it's a bit more of a free-for-all. For U.S. national team players and former MLS players, the league keeps an "allocation order," like the waiver list in baseball, and the team at the top of the order has the first crack at signing the player. For players who don't meet that criteria, each team is required to maintain a seven-player "discovery list." The team that first put any player on its discovery list has priority to sign him — though in most cases, individual clubs work out their own deals for foreign players, and if another team has priority, they trade something to that team in exchange.

If that all makes sense, congratulations! You're ready to dive into the rest of the league's nonsensical rules, like the ones regarding "Targeted Allocation Money." For most of us, though, knowing about designated players, homegrown players, and the discovery list is probably enough for a start — and we have only until next spring to get up to speed.

Brian Stensaas — Star Tribune, Star Tribune

SHORT TAKES

• More proof that pro soccer fits in Minnesota: just like their local counterparts in other leagues, Minnesota has had a terrible time of things in championship games. Since turning professional in 1994, Minnesota's various teams have made six league finals — and lost four of them. Only New England, which is zero for five in MLS Cup finals, has more title-game losses.

• The preview of the big European leagues, apart from the Premier League, is pretty simple: Bayern Munich will win the Bundesliga, Juventus will win Serie A, Paris Saint-Germain will win Ligue 1, and either Barcelona, Real Madrid, or Atletico Madrid will win La Liga. Also, one of those six teams will win the Champions League. All of these are yearly occurrences, and there's no reason to believe this year will be any different.

• Maple Grove native Cody Cropper, who had been playing in England for MK Dons in the second division, is returning to American shores. Cropper signed with New England this week, his first American contract after four professional seasons in England.

WEEKEND WATCH GUIDE

Premier League: Arsenal at Leicester City, 11:30 a.m. Saturday, CNBC. Last year's Premier League top two are already in crisis; both lost in round one, and neither has much confidence going into week two. Leicester City lost just three times in its magical season last year, but two of those were to Arsenal; the Gunners sorely need another win to get their season started.

MLS: Los Angeles at New York City, 2:30 p.m. Saturday, ESPN. MLS loves showing off New York vs. Los Angeles. To the league's delight, NYC is leading the Eastern Conference in its second season, while Los Angeles is (as always) chasing the title in the west. This game has more big names than any other on the MLS calendar, and you can expect to hear plenty about them.

Liga MX: Atlas at Chivas, 9 p.m. Saturday, Univision. This is the cross-Guadalajara rivalry, and like any good soccer rivalry it's got a history in a class war. Atlas are the upper-class team, Chivas the team of the people. Things haven't exactly cooled down in recent years; when the two teams met in the 2015 playoffs, Atlas fans started a riot after Chivas went ahead 4-1.

MLS: Portland at Seattle, 8:30 p.m. Sunday, FS1. The Sounders fired head coach Sigi Schmid, but maybe more importantly, simultaneously signed Uruguayan attacking midfielder Nicolas Lodeiro. All the new arrival has done is spark his new team to seven points in three games, and now Seattle trails rival Portland by just five points for the final playoff spot.

Writer Jon Marthaler gives you a recap of recent events and previews the week ahead. • jmarthaler@gmail.com

Online: startribune.com/soccer