There may be only one David Beckham, to paraphrase the chants of soccer fans in England, but Major League Soccer will allow teams to sign a second superstar under the so-called Beckham rule.

In an announcement on Thursday, the league said that it was expanding the designated player rule to give clubs the chance to sign two players above the M.L.S. salary cap, and that it would also give teams the option of purchasing a third slot for $250,000.

“It represents a continued commitment by the league to see that there are mechanisms in place to improve the quality of play and improve the product on the field,” Todd Durbin, the league’s executive in charge of player relations and competition, said in a conference call Thursday. “The driving force behind it is to allow teams that want the ability to build their roster around high-profile players to have the ability to do that, but do it in a way that is competitively neutral.”

Under the previous version of the rule, a club could sign a player for however much it could negotiate, but only $415,000 of the player’s salary would count toward the salary cap. The new rule will reduce that amount to $335,000 for first and second designated players. If a club chooses to purchase a third slot, that player would also be valued at $335,000 under the salary cap. If a player joins midseason, his salary would only count $167,500 toward the cap. The $250,000 fee for purchasing a third slot would be distributed to clubs who do not already have three designated players. Durbin said teams may “buy down” the amount counted against the salary cap by using allocation money, another peculiarity of the M.L.S. structure. The D.P. slots, which could be exchanged, are no longer tradable under the new rules.

“We will continue to see varied approaches from our clubs in assembling their rosters, and these changes will give them increased flexibility,” Durbin said in a statement.

The new rule, which allows teams to sign up to three star players at a cost of more than $1 million under the league’s salary cap, comes after M.L.S. and the players union agreed to a new collective bargaining agreement that increases the cap more than $200,000 from last season to $2.55 million.

When asked why the league decided to add D.P. slots instead of further increasing the overall salary cap, Durbin said the two decisions were complementary.

“There is recognition on behalf of the league that there needed to be an increase of the salary budget,” Durbin said. “We don’t think about it as an either/or.”

He added: “All of these issues are certainly interrelated.”

Beckham, who was signed by the Los Angeles Galaxy in 2007, was the first marquee foreign star signed under the designated player rule. After Beckham, a former England captain, joined the league with much fanfare, the Brazilian Denilson signed with F.C. Dallas. He was largely a disappointment and left M.L.S after one season. Juan Pablo Angel, the Colombian forward, signed with the Red Bulls in 2007, and the Mexican talisman Cuauhtémoc Blanco was a key member of the Chicago Fire until his departure after the end of the 2009 season. Claudio Reyna was the first American designated player in the league when the former United States international signed with the Red Bulls in 2007 (the team was able to sign a second D.P. after trading the rights to Amado Guevera).

There are currently six designated players in M.L.S., and Landon Donovan of the Galaxy is the only American D.P. While some of the foreign signings have been key contributors to their teams (Angel, Guillermo Barros Schelotto of Columbus and Freddie Ljungberg of Seattle come to mind) others (like Denilson and Argentina’s Marcello Gallardo, who played one injury-plagued season with D.C. United) have failed to make much of an impact.

What do you think of the new M.L.S. designated player rule?