CHICAGO -- Craig Kimbrel was firing baseballs into a net inside a barn on his property at one point during his offseason. A friend of his walked by and the pitcher invited him to stand next to the plate, giving Kimbrel the visual of a batter for his workout.

The next day, his friend had carved a makeshift hitter out of plywood and propped it up in front of the netting.

"I guess not everybody likes standing in," Kimbrel said with a laugh.

The Cubs are hoping that continues to be true for Major League hitters, who have been tormented by Kimbrel's rising heater and knee-buckling curve for years. On Friday, Chicago officially unveiled Kimbrel as its newest addition, signing the closer to a three-year contract that is worth $43 million guaranteed and could keep him in a Cubs uniform through 2022.

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Kimbrel was the most logical target for the Cubs over the offseason -- given the team's need for an impact late-inning arm -- but circumstances did not allow the move to happen until now. The team's play through the first two-plus months was a crucial component. Logistics, however, also played a big role. The Cubs had more financial wiggle room now than over the offseason, and Kimbrel's signing no longer included Draft-pick compensation.

"We saw it as a unique opportunity," Epstein said. "How often can you add an elite closer like Craig, somebody who's arguably on a Hall of Fame trajectory, with the need that we have midseason, without giving up any prospects? That's just such a great opportunity for the Cubs.

"We all sat down and said, 'If there's a way to make this happen, we want him to be wearing a Cubs uniform.'"

That uniform was handed to Kimbrel in a news conference at Wrigley Field prior to Friday's game against the Cardinals. The number on the back was "24" -- a change from the "46" he has worn his entire big league career. That digit currently belongs to Pedro Strop, who will revert to being the Cubs' main eighth-inning man upon Kimbrel's arrival to Chicago's bullpen.

That is a process that could take up to three weeks.

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Kimbrel will throw a bullpen session on Saturday in Chicago before flying to Arizona to continue his workouts at the team's complex. The right-hander will work through a series of bullpen sessions and live batting-practice outings before transitioning to Minor League games. The Cubs have technically optioned Kimbrel to Triple-A Iowa to buy him time to work through the buildup program.

In order to add Kimbrel to the 40-man roster, the Cubs transferred reliever Allen Webster (radial nerve inflammation) to the 60-day disabled list.

"We've sat down, we've put a game plan together," Kimbrel said. "But at the end of the day, it's based off how I recover, how I get ready. This isn't about getting back on the field as fast as I can. This is about being the best that I can be in October and down the stretch and doing what I came here to do for this team."

Kimbrel said that he spent most of his time training at Montverde Academy outside Orlando, Fla. He had a trainer there for workouts and top-notch baseball facilities, which alum Francisco Lindor helped create through substantial donations. Kimbrel said one of the high school catchers helped out with some mound sessions.

"He was great," said the pitcher. "We might see him one day."

Kimbrel, 31, has a career 1.91 ERA to go along with 333 saves and 14.7 strikeouts per nine innings over nine seasons in the Majors. Last season, the right-hander had a 2.74 ERA with 96 strikeouts against 31 walks in 62 1/3 innings for the Red Sox.

Epstein said they sent a scout, alongside "super scout" David Ross, to watch Kimbrel throw a bullpen session a week ago. Ross actually caught Kimbrel in the closer's Major League debut with the Braves in 2010, and the former Cubs catcher spent a lot of time talking to the pitcher about the environment that manager Joe Maddon, Epstein and the players have created in Chicago.

"It's the Chicago Cubs," Kimbrel said. "He didn't have to tell me all that much about the culture of this place and what's expected here."

Kimbrel will earn $10 million this year, followed by $16 million in both 2020 and '21. If his option for '22 does not vest, the Cubs will have a $16 million club option, or a $1 million buyout, for a fourth year. There will be salary coming off the books in the upcoming seasons, but the Cubs made it known since early in the offseason that there was little financial wiggle room for this year.

Part of the payroll equation was altered when 38-year-old veteran Ben Zobrist was placed on the restricted list on May 8 to tend to a family matter. Zobrist's return this season is uncertain, meaning Chicago would have north of $9 million of his $12.5 million '19 salary to reallocate if he is not activated for the remainder of the season. Epstein has maintained contact with Zobrist, but there is still no timetable.

"We're here for Ben," Epstein said. "He's part of the Cubs family, and he knows that the door is open for him if it's ever an appropriate time for him to return. It'd be wonderful to see both those guys wearing Cubs uniforms together at the same time."

Even with the unexpected budget room, the Cubs had to play well enough to convince the front office to go all in on this type of transaction this early.

"If we're not playing that well and our record is a little bit different," Cubs pitcher Jon Lester said, "I think that probably changes their outlook on things. … [The front office] stepped up big for us. That's a huge thing for us."

Epstein noted that he addressed the team Friday morning not only to introduce Kimbrel, but also to credit the players for doing their part in making this addition happen.

"The job they've done the first two months of the season," Epstein said, "playing really good baseball and putting us in a great position, led us to do what contending teams do, which is look outside for help. We think that this team certainly has a chance to accomplish our goal, which is win the World Series."