But for every player who tastes a measure of success after leaving -- such as Clint Dempsey, currently Fulham's leading scorer, and Maurice Edu, now getting more regular minutes at Rangers -- there are others who have difficult experiences. Former Chicago Fire star Damani Ralph, for instance, struggled to find playing time with Russia's Rubin Kazan, suffered a series of injuries and now finds himself without a team at all.
While soccer in the U.S. is still generally disparaged abroad, there's growing recognition that the sport is improving here. "[David] Beckham went straight in to playing with Milan," Seattle Sounders midfielder Freddie Ljungberg said. "That shows that the league isn't that bad."
Ljungberg, of course, played for Arsenal for many years. Yet the Seattle player who may be the most eager to gain the attention of European clubs could well be another Fred -- Fredy Montero.
The 21-year-old Colombian striker, on loan from Deportivo Cali, has been an early revelation for the Sounders, scoring three goals in his first two games. Although those performances reveal Montero's commitment to performing well, he says it wasn't the lure of MLS specifically that drew him to sign with the Sounders.
"In Colombia, there's little [known] about the league," he said after Seattle's loss to Chivas USA on Saturday. However, he did cite other Colombians' success in the U.S. as a major factor for his decision. "I did know that Juan Pablo Ángel and Juan Toja were here and that it had gone well for them."
Both Toja and Angel made the All-Star team in their first MLS seasons. Montero was hoping for similar success and also looking to learn from the MLS style.
"This will be important for me and my career and my future," Montero said. "The rhythm is completely different. I've had to adjust. The soccer here is more physical, fast and intense. [In Colombia] they have more touch, more technique and it's slower."
To suceed in most European leagues, however, players must be able to handle physical, tough play. That's something MLS offers regularly. "I noted the difference as soon as I got here," Montero said. "I think that change has been good for me. I hope I'll adjust to this level and continue to score goals."
It seems logical that if you score goals in MLS, you attract overseas attention. But that's not a given. When Carlos Ruiz joined the league in 2002, he was a brash young forward who scored an eye-popping number of goals (24) and helped the Los Angeles Galaxy secure their first MLS Cup championship. Yet not only did Ruiz fail to garner a decent offer from a club abroad, but he also eventually was unable to even stay in MLS, washing out of the league after the end of last season.
Besides scoring ability, European clubs are interested in players who have at least one dependable, world-class skill. For Eddie Lewis, that was his ability to cross the ball. For Tim Howard, his shot-stopping ability in goal. For Ryan Nelson, his leadership. Without that "plus tool," that something extra, overseas coaches won't see an incentive to help a player overcome any other deficiencies.
Sometimes, a player can be too successful in MLS. Often the league, which owns all player contracts, won't sell a player to a European club if an offer comes in that administrators deem inadequate. Before Dempsey joined Fulham, Charlton Athletic had offered a contract for the former New England star. But MLS rejected the offer as too low, leaving Dempsey feeling frustrated before things were finally settled with Fulham.
In order to avoid any situation in which MLS could control his future, U.S. defender Carlos Bocanegra played out his first multiyear MLS contract so he could offer himself to clubs abroad as a free agent. For a while, he was Dempsey's teammate at Fulham.
Ljungberg is confident Montero has the tools to make the jump -- with certain qualifications. "In a couple of years, he'll get better and better and then he'll be ready for Europe," Ljungberg said. "He has the potential to be able to play in Europe, but maybe he should wait a little bit and develop a little bit more."
Off-the-field distractions aren't helping Montero either. He is still feeling the effects from facing a recent sexual-assault accusation. Though prosecutors declined to file any charges, citing a lack of evidence, the incident cast a pall over the Sounders' bright start to the season. Since the allegations came to light, expansion Seattle is on a two-game losing streak after opening 3-0-0.
"We've done a pretty good job of keeping focused," head coach SigiSchmid said about Montero's situation. "I think it's obviously been harder on Fredy than anyone else. He's got our support and hopefully as time goes forward, it will be an easier thing."
If Montero can sustain his early form, he may be a top candidate to move on from MLS. Though a bit on the small side at 5-foot-9, his ball control, speed and knack for delivering bending balls that goalkeepers struggle to read make him a special sort of player -- someone who can create a goal out of almost nothing.
Youth also gives clubs a high upside when they consider investing in potential. That's part of the reason the highest transfer fee paid in MLS history was $10 million for Jozy Altidore, who, at age 18 last summer, became the youngest player MLS has sold. True talent can also be spotted quickly, even on a struggling team -- Edu was sold after only a season at Toronto FC.
"I'd like to play internationally for Colombia, and also on a club in Europe," said Montero, adding that the mix of players in MLS appealed to him as a place to learn. "I think the change and learning to play against different styles here will help me get there. "
The countdown has started.