All the money the Seattle Sounders have been banking with those huge CenturyLink Field attendances? They’ve paid off with one of the bigger transfer gets in Major League Soccer history, one that’s seen the club guarantee $41 million to bring U.S. international Clint Dempsey to Seattle.

Multiple sources within Major League Soccer have informed NBC Sports’ ProSoccerTalk that Tottenham Hotspur will receive a $9 million transfer fee for the U.S. captain’s services – roughly 95 percent of the £6 million Spurs reportedly paid for Dempsey last summer. To complete the unexpected move, Seattle have guaranteed the 30-year-old attacker $32 million over the next four seasons, making him one of the most expensive players in league history.

Dempsey’s base salary will eclipse that of David Beckham and Thierry Henry, though other facets of Beckham’s contract gave him a percentage of the Galaxy’s revenue. The $32 million, however, is the largest base salary commitment a player has ever received from an MLS franchise.

The $9 million transfer fee will also be the highest paid in league history and the second major purchase made by the Sounders this summer. Seattle paid La Liga’s Levante $4 million to get striker Obafemi Martins out of his contract.

As a Designated Player, the former New England Revolution attacker will not have to go through the allocation process, to which internationals like Sounder Eddie Johnson and newly signed Chivas USA defender Carlos Bocanegra were subjected when they returned to MLS.

Dempsey was originally seen flying to Seattle last night, with rumors of Seattle’s connection to the U.S. international circulating Thursday morning. On Friday, ESPN originally reported Dempsey’s agreement with Seattle, with ProSoccerTalk confirming the story shortly there after.

Dempsey is set to return to the United States after six-and-a-half seasons in the Premier League, all but one of which were spent at Craven Cottage. During his time in England, Dempsey scored 72 time in 268 all-competition appearances, including a 23-goal season in 2011-12 with Fulham.

Tottenham Hotspur acquired the former Cottager on transfer deadline day last August, with Dempsey immediately moving into André Villas-Boas’ starting lineup. While his playing time decreased as the season progressed, Dempsey still scored 12 times in 43 all-competition appearances, his third-highest goal total since leaving New England in 2006.

He joins a Seattle Sounders team that sit seventh in the Western Conference, threatening to miss the postseason for the first time in franchise history. The addition of Dempsey, however, will bolster an attack that’s 14th in Major League Soccer in goals scored, one that already features fellow Johnson and Martins.

How Dempsey fits with those two strikers remains to be seen; however, Thursday on Seattle-based radio station KJR, Sounders head coach Sigi Schmid said the team was looking for a central or attacking midfielder to fill the Designated Player spot freed up by Shalrie Joseph’s renegotiated contract. Capable of playing in an attacking midfielder’s role, Dempsey could allow Schmid to incorporate his new star without sacrificing any of his existing goal scorers.

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