It can be a little difficult to explain international soccer's transfer system to fans of American sports, who are used to trades and drafts and free-agent signings.

Soccer players are almost always bought and sold, instead of being traded for other players. For the right price, virtually any player who's under contract is available — and the player has to agree to the move, too. You can think of it as free agency, except every player is potentially involved, whether under contract or not.

This creates a delicate three-way dance between selling clubs, buying clubs, and players. The selling club may not want to sell, but doesn't want an unhappy player on its hands — and can get much-needed funds by selling at a high price. At Sevilla, in Spain, the club has completely remade itself by selling players. In the early 2000s, Sevilla faced huge debts and had been relegated to the second division. Thanks to judicious buying and selling, the club has climbed back into the Spanish elite while turning a profit.

Then there are the buying clubs, highlighted by those with seemingly endless funds: Real Madrid, Barcelona, Manchester United, Chelsea, Manchester City, Bayern Munich, and Paris Saint-Germain. No price is too high for these teams, meaning that they almost always get the players they want. That said, selling clubs tend to vastly increase their prices when one of these teams is after a player, making yearly outlays of more than $100 million a routine proposition for the teams with ridiculous money.

There used to be just a handful of other rich English teams, such as Arsenal, Liverpool and Tottenham, that could compete financially for players throughout Europe. Thanks to the new, lucrative Premier League TV contracts, the rest of the Premier League can now also be said to be a step below the above teams. Alongside traditional powerhouses in Europe's other big leagues, every top-division English team is now in the running for players, and has money to burn.

For players, this financial explosion is good news. Negotiations over future contracts are part of the process, and for players, transfers usually mean a bigger paycheck and a more prestigious team. Take the case of Belgian striker Michy Batshuayi, who scored 17 goals for Marseille last year. Premier League strugglers Crystal Palace agreed to a $42 million fee with Marseille, but Batshuayi turned them down, not wanting to fight against relegation next year. Instead, he agreed to go to Chelsea for a similar fee, where he has a chance to compete for a title next season.

Tom Wallace — STAR TRIBUNE, Star Tribune

The transfer window — the period in which teams can buy, sell, and sign new players — is already open for the summer, and like Batshuayi, we've already seen a few moves. Brace yourself for more. There is plenty more money out there to be spent.

SHORT TAKES

•  The annual Schwan's USA Cup youth soccer tournament kicks off next weekend in Blaine, with yet another record-breaking number of teams. 1,178 squads, from 19 states and 19 countries, will play over the course of the week at the National Sports Center, which now has 54 fields at its sprawling complex. Minnesota United FC will also host three games at the NSC during the tournament, which runs from July 15-23.

•  France takes on Portugal in the final of the European Championship on Sunday, as Portuguese attacker Cristiano Ronaldo tries to drag an unremarkable Portugal team to his first international trophy. You can expect Portugal, first and foremost, to try to keep France off the scoreboard; in three knockout-round games, the Portuguese have allowed just one goal.

• Spare a thought for Woodbury's Kassey Kallman, who has played the entirety of the past 32 consecutive games for the Boston Breakers in the NWSL. Kallman's streak makes her the league leader in consecutive minutes, which is impressive. Boston, which has one win in 11 games and has scored just three goals all season, isn't.

WEEKEND WATCH GUIDE

Friendly: U.S. Women's National Team vs. South Africa, noon Saturday, FS1. For most tournaments, national teams are allowed 23 players on the roster. For the Olympics, though, only 18 players can go — making every roster spot precious. National team coach Jill Ellis has just two matches, including this one, to make her final decisions about who will defend the USA's gold medal.

MLS: Los Angeles at Seattle, 2 p.m. Saturday, ESPN. Seattle has been a perennial powerhouse in the Western Conference, but at the midway point of this season, coach Sigi Schmid is on the hot seat. Despite the arrival of wunderkind forward Jordan Morris, the Sounders have scored the fewest goals in the league and are ninth out of 10 teams in the West.

Euro: France vs. Portugal, 2 p.m. Sunday, ESPN. As it has been for this whole tournament, France is the favorite to win the title. The Euros have been characterized by boring, careful soccer, but France — led by Antoine Griezmann (six goals) and Olivier Giroud (three) — has the difference-making attacking flair that almost every other team has lacked. Expect a home win at Stade de France.

MLS: New York City at Sporting Kansas City, 7 p.m. Sunday, FS1. Don't look now, but NYC is leading the Eastern Conference. The team's three highly-paid European veterans, Frank Lampard, Andrea Pirlo, and David Villa, have endured much criticism for lack of production — but the three have lead NYC's charge to four consecutive wins, with a combined six goals.