Terrence Boyd, left, who has recently seen action for the U.S. men’s soccer team, has played in 63 games for Borussia Dortmund’s reserve team over the last two seasons in Germany. MLS hopes to replicate such a system. (STEVE NESIUS/REUTERS)

Using one measure, U.S. soccer is healthier than ever. High-profile players such as Clint Dempsey and Tim Howard are blossoming in European professional leagues, giving American soccer a pedigree it has long sought.

Yet while European leagues provide a platform for a growing percentage of American players, the maturation of U.S. soccer is inexorably tied to Major League Soccer, which serves as the training vehicle for most of the country’s top young players. The more players who mature in the domestic league, the deeper the U.S. pool becomes.

At a time when MLS is touting its development of young professionals through so-called “homegrown” signings, a majority of those prospects are not getting on the field. Some have been outright discarded.

Of the 52 homegrown players — prospects from MLS youth academies signed to professional contracts — who have signed with MLS clubs since 2008, 27 failed to make any league appearances in 2011 or thus far in the 2012 season. Eight have been released.

Without a functional system in place to give such players actual game experience, MLS risks stagnating their development, thus also likely curbing the long-term growth of the American player pool.

“That is definitely a concern,” U.S. men’s national team coach Juergen Klinsmann said during a conference call with reporters on April 4. “And it’s definitely a topic we want to bring up with [MLS Commissioner] Don Garber and MLS because we want to make sure that especially younger groups of players get as much exposure as possible coming through their developmental stage.

“I know that an 18-, 19-, 20-year-old is not at the same level as an experienced player and a proven player, but we’ve got to make sure that they get the chance to break through and get their minutes in.”

Languishing on the bench

MLS teams founded academy systems to recruit top players from their designated territories. An MLS team, in theory, would provide better coaching and a better environment to develop players than club teams or high school programs. The young players would benefit by coming up in a professional atmosphere, at times practicing and interacting with MLS players, coaches and administrators while playing games against other MLS youth teams and top club-level teams in the U.S. Development Academy, a league founded in 2007 by U.S. Soccer.

The academies aim to mimic a structure similar to those used around the world, where professional clubs cull new talent from within — famously so at Spanish giant Barcelona’s La Masia academy and the Dutch powerhouse Ajax academy.

In 2008, MLS created a “homegrown player” initiative in which clubs could sign players who had participated in a club’s youth development academy for at least one year. Those homegrown players would not count against the salary cap and teams would receive a larger percentage of any transfer fee if the player were sold to another club.

The rule gave players a more direct route to a professional contract in the United States, while incentivizing MLS teams to develop and sign local players.

“That is the mandate of the system,” said Todd Durbin, MLS executive vice president of player relations and competition. “To be in that market with a goal of developing players.”

The problem arises when young players sign contracts but are not yet ready to play in MLS games. Under the current system, homegrown players who have signed contracts with MLS teams have few options for top-flight competition other than MLS reserve league games, which have been canceled at times this season because of a lack of available players.

The MLS competition committee is looking into two remedies aimed at increasing playing time for younger prospects, the first being an expansion of first-team rosters and increasing the number of reserve league games.

The second option is to create something of a minor league affiliate system in partnership with the second-tier North American Soccer League and the third-tier United Soccer Leagues.

This would more closely mimic the system employed in Europe, where it is customary for younger prospects to spend the majority of their time with reserve teams that are run by the top-level clubs but play in lower pro divisions.

The lower-tier teams provide an ideal venue for young prospects to get significant minutes in games. American Terrence Boyd, for example, has played in 63 games for Borussia Dortmund’s reserve team over the past two seasons in Germany. At age 21, he has yet to make his debut for Dortmund’s first team, but he started in a recent friendly for the U.S. national team under Klinsmann.

The goal is to “deal with the transition time from youth soccer to first-team soccer” more effectively, Durbin said.

Currently, the lower-tier leagues operate independently of MLS, though some clubs, such as D.C. United, have loaned players to NASL or USL teams. United midfielder Conor Shanosky, a homegrown player who has played for the U.S. under-20 team, is on a season-long loan to the Fort Lauderdale Strikers of the NASL, while third-string goalkeeper Andrew Dykstra went on a one-month loan to the Charleston Battery of the USL.

“Ninety percent of 18-year-olds aren’t ready to play for a first team in MLS,” Real Salt Lake General Manager Garth Lagerwey said. “They desperately need games and training. We have to have some version of a second division. If that means partnering with USL and NASL with free player movement between [the leagues] . . . I think that would be ideal.”

‘We’re inefficient’

As it stands, many homegrown MLS players are languishing on the bench during vital developmental stages. Of the 27 homegrown players without a league appearance in the last season-plus, 20 are under the age of 21.

Former U.S. national team coach and current L.A. Galaxy boss Bruce Arena said it’s an issue that must be sorted.

“We’re inefficient in how we allocate resources in the academy,” Arena said. “There’s a likely argument where you can say we have improved the ability to move kids to the age of 17 or 18. Where do they go from there? It’s a black hole. It’s insane. We should have a USL-type of league [to develop players]. Right now, the kids would be better off going to college, and then we are back to the same thing again.”

Said Klinsmann: “We need to find a tier-driven environment because we need to give a lot of the younger players the opportunity to get enough games per year. . . . It’s really worth it to get everybody at the same table sooner or later and discuss all those topics.”

Staff writer Steven Goff contributed to this report.