The Red Sox have officially signed heralded Cuban infielder Yoan Moncada to a minor league contract, the team announced. Terms of the deal weren’t announced, though Moncada reportedly received a $31.5MM signing bonus according to Joel Sherman of the New York Post (Twitter links).

Because Boston had already exceeded its bonus pool for the 2014-15 international signing period, the team will pay a full 100 percent tax on Moncada’s bonus, bringing the total cost for his services to $63MM. On top of that, the Red Sox will now be restricted from signing any international amateur for more than $300K in the 2015-16 and the 2016-17 international signing periods.

Moncada, a 19-year-old switch-hitting infielder, is the most sought-after international prospect in recent history. Said to be a true five-tool talent, scouts have likened his upside to that of Robinson Cano and Chase Utley (in his prime). Prospect specialists at Baseball America, MLB.com, Baseball Prospectus and Fangraphs have all suggested that Moncada would rank in the top five to 15 prospects in Major League Baseball upon signing, which will make him Boston’s new No. 1 prospect. Unlike recent Cuban signings such as Jose Abreu and Rusney Castillo, however, Moncada will likely require at least one season in the minors — possibly two.

Over the past several months, the Red Sox have been one of the primary teams connected to Moncada, although many believed the Yankees and Dodgers to be in a better position to land him, as the Red Sox don’t have a clear long-term need in the infield with Dustin Pedroia at second base and Pablo Sandoval entering the first of a five-year, $95MM contract. (Sandoval, of course, could move over to first base in a few years.) Xander Bogaerts figures to be the long-term answer at shortstop, though the expectation among scouts is that Moncada will end up at second, third or possibly in center field (where Castillo is currently slotted).

As Sanchez wrote last week, the overage tax must be paid to the league in full by July 15, whereas the bonus can be paid out in installments over the course of the next three years. It’s not known at this time whether or not the Red Sox made the best offer, but agent David Hastings did say recently that size of the bonus would not be the sole determining factor in choosing a team. Moncada also had private workouts for the Yankees, Dodgers, Padres, Brewers, Rays, D-Backs, Tigers, Giants, Rangers and Cubs (though the last two would have been ineligible to sign him until July 2, as they had incurred maximum penalties in the 2013-14 international signing period, thereby restricting them in the 2014-15 period).

With this agreement, Moncada has absolutely shattered the previous record signing bonus for an international amateur. That distinction was held briefly by infielder Roberto Baldoquin, following his $8MM bonus from the Angels earlier this winter, and then held even more briefly by right-hander Yoan Lopez, who received an $8.27MM bonus from the D-Backs. The size of Moncada’s bonus will likely come up in discussing the next collective bargaining agreement, as it figures to be a major talking point among proponents of an international draft.

MLB.com’s Jesse Sanchez was the first to report Moncada’s deal with Boston (via Twitter).