How Rusney Castillo came to Boston

— -- BOSTON -- In his native Cuba, 27-year-old Rusney Castillo is known as "La Pantera" -- the Panther.

He is Puig Lite, in the words of one  Boston Red Sox  talent evaluator, adding that at 5-foot-9 and 205 pounds, Castillo is not as big as Dodgers star Yasiel Puig but has a powerful, compact body like Ron Gant , the former Brave. Fellow Cuban Yoenis Cespedes modestly has told confidants that Castillo is a better player than he is, according to another source.

Castillo has plus-plus speed, according to multiple teams that worked him out privately, able to navigate 60 yards in less than 6.5 seconds, according to one evaluator. "He's a flyer," the evaluator said.

He has plus-plus power, in the view of the Red Sox. "He's a free swinger who's not going to walk a lot, a pull hitter who will hit them so far over the Monster it will be crazy," said the evaluator. "And he has the power to reach the bullpens in right field."

That sentiment is not shared by every club that scouted him.

"We think he can hit 15 to 20 home runs, which these days may be plus power," said a talent evaluator for another club that had keen interest in him, "but we don't see him having 30-homer power. Hey, we could be wrong."

He has the hands and sufficient arm to play center field, the position he played on Cuba's national team until he was suspended for what the Cuban government termed a "violation of the code of ethics of revolutionary baseball."

Coming to terms on a seven-year, $72.5 million deal with Castillo was the result of a months-long project spearheaded by Allard Baird, the team's vice president of player personnel.

Baird forged a relationship with Castillo, his handlers and his agents, almost from the time he defected from Cuba and established residency in Haiti last winter. Baird, with assistant director Jared Banner, stayed in touch with Castillo almost to the moment he signed.

"There was no stone unturned with Allard," one Sox source said Friday. "He knows everything about the kid."

Director of player personnel Dave Finley and special assignment scout Galen Carr went to see him last winter in the Dominican Republic. Eventually, a half-dozen or so Sox scouts, including international scouting director Eddie Romero and Latin American coordinator Todd Claus, saw him there. The Sox sent a contingent that included general manager Ben Cherington, Baird and special assignment scout Marc Wasinger to watch him at his showcase last month at the University of Miami, attended by 28 of 30 big league clubs.

For his private workout that followed in Fort Myers, the Sox had a full complement of evaluators present, led by Cherington and including special assignment scout Eddie Bane. Members of the team's video and medical staffs were also present, and the Sox arranged for pitchers to throw to him.

And they all watched all the video of Castillo playing in Cuba that they could get their hands on.

The process was an exhaustive one for the Sox, and a stressful one for Castillo, who went through a number of private workouts for clubs.

A week ago Friday, Castillo's agents -- he is represented by Jay Z's Roc Nation Sports -- asked teams to submit their best offer. One of those teams was the Detroit Tigers, whose general manager and president, Dave Dombrowski, acknowledged having considerable interest in Castillo.

On Monday, Dombrowski said, Castillo's agents called and said the Tigers were out of the running, even as reports persisted that the Tigers were finalists, a belief held by some in the Sox front office. Dombrowski, reached by phone on Friday, said he didn't say anything at the time because of his unfamiliarity with the agents. There was a possibility, he said, that they could call back and say they'd changed their minds.

"They were honest," he said. "We were out."

The Sox had fallen short in their pursuit last winter of Cuban strongman Jose Abreu, but the circumstances were different. They were coming off winning the World Series, and they had a popular incumbent at first base in Mike Napoli, a free agent. Signing Abreu instead of Napoli would not have been popular in the Sox clubhouse, and if Abreu proved a bust, the fallout would have been considerable.

With Castillo, the Sox were looking to rebuild an outfield that had been historically inept offensively, and had a free shot to do so -- they would sacrifice no players nor draft choices, only money. At worst, the Red Sox believed, Castillo would become an average major league player, with a better chance of blossoming as a star. Either way, an investment that averaged just over $10.3 million annually represented a bargain.

This was one auction they were determined to win, and late Thursday night, they forged the outlines of an agreement. By Friday morning, headlines in his native Cuba proclaimed that "La Pantera" had signed with the Sox, and U.S. media outlets soon followed.

By midday Friday, Castillo was on a plane to Boston, where he is scheduled to undergo a physical Saturday. Once he has passed his physical, only then will the Sox officially announce the deal is done.

But for all their confidence that they had scored a coup in signing Castillo, the Sox talent evaluator added a caveat: Castillo has not played in a game for nearly a year and a half. There is only so much evaluation you can do at a workout on an empty diamond in the Dominican, a showcase attended by dozens in Miami, a private workout in Fort Myers, or off a video.

There is risk involved. There is comfort in observing the success of other Cuban defectors like Cespedes, Puig and Abreu, but the risk has to be acknowledged.

"We've all talked to him, even if it was just for five minutes," the talent evaluator said. "We've all seen him in person, seen him on video. But he hasn't played in a game since 2012. We saw him in international tournaments back then, but haven't seen him in a game since.

"I guarantee if you watch him take BP, or watch him run -- he runs as good as anybody in the league -- you will see what we saw. But can he hit in games? We saw him in maybe 30 live at-bats. Hopefully, we saw him for what he is, but there's a risk.

"We'll see. We think it was a good gamble."