MINNEAPOLIS -- Nelson Cruz said to Twins senior director of communications Dustin Morse at the end of Spring Training that he planned to hit his 400th career home run this season -- and to expect playoff baseball in October at Target Field.

Cruz didn’t let age stand in his way. Cruz didn’t let a recurring wrist injury stand in his way either, even after he ruptured a tendon. On Sunday, he made one of those predictions come true and pushed the Twins closer to the next.

• Every member of the 400-HR club

Cruz crushed an opposite-field solo homer off Kansas City reliever Gabe Speier in the fourth inning to become the 57th member of Major League Baseball's 400-homer club. Led by Cruz's big swing, two towering homers from Miguel Sanó and three RBI doubles from Eddie Rosario, the Twins closed their regular-season home schedule with a 12-8 win over the Royals.

• Box score

The victory reduced Minnesota’s magic number to clinch the American League Central to three, and it stayed there after the Indians defeated the Phillies in the evening.

“It's nice to do it in front of the fans,” Cruz said. “I think they deserve it. They've been such a big influence for us as a team. They come up every day with that energy. Even when we're behind, they give us that energy to step up and do good things."

The blast made Cruz the ninth Dominican-born player to reach the 400-homer milestone, joining Albert Pujols, Sammy Sosa, Manny Ramirez, David Ortiz, Adrián Beltré, Vladimir Guerrero, Edwin Encarnación and Alfonso Soriano. It also marked Cruz's team-leading 40th bomb of the season, joining Barry Bonds and Hank Aaron as the only players in MLB history to hit the feat at age 39 or older.

"Growing up, I never thought to be able to hit that many home runs," Cruz said earlier this week. "It's definitely a blast to be a part of baseball history. So it's just, I guess, one season at a time, grow to the moment."

Cruz is the 26th player in MLB history with at least four seasons of 40-plus long balls after having reached the mark in 2014, 2015 and 2016. He is also the third player in Twins history to go yard 40 times in a season, joining Hall of Famer Harmon Killebrew and Brian Dozier.

That's how the history books will remember Cruz, anyway.

It's a different story in the Twins' clubhouse. Sure, Minnesota's leadership brought the 39-year-old Cruz in to fill the vacant designated-hitter role and, of course, to hit lots of dingers. In that regard, he has more than delivered on expectations.

But as the Twins understood when they brought him in to lead their talented stable of young rising stars this past offseason, Cruz's impact on his teammates behind the scenes has proved just as valuable -- if not more so -- than his steady stream of roundtrippers.

"[The milestone is] more fun because of the person he is," hitting coach James Rowson said. "We get to, obviously, spend time with him as a family and spend time around him talking. This guy's just a special human being. So, it’s more fun when you see a really good person be able to accomplish really cool things in this game."

It’s impossible to quantify what Cruz has meant to this clubhouse. It began in Spring Training, long before the Twins began to break Major League records left and right, when he brought the club together by delivering a speech in which he declared that other teams would be scared of them this season.

Throughout the year, Cruz has monitored the pulse of the clubhouse and has chosen moments to address his teammates when he has felt necessary. Notably, he made a speech when the Twins briefly fell into second place in the division for a day. (Minnesota is 25-13 since then.) Most recently, he addressed the team before its final trip to Cleveland. (The Twins immediately swept a season-defining doubleheader behind 18 innings from the bullpen.)

Cruz also floats around the clubhouse, cracking jokes, offering bits of advice and wisdom, and maintaining comfortable, loose relationships with players and coaches alike, while setting an example through his steadfast preparation that teammates have raved about all season.

“I think we're all learning [from Cruz] every day,” Rowson said. “Getting to watch him, and watch him go about it, and see how he frames things. He could talk hitting, and he could say things and simplify some things. And I'll hear him say something, and go, 'Man, I didn't think of it that way.’ … Nelson's a one-of-a-kind type of player, man.”

That impact is particularly evident in the continued progression of Miguel Sanó, who has lockered next to Cruz throughout the season to foster a bond between the pair of Dominican sluggers. Sanó’s two homers on Sunday stretched his season total to a career-high 33, and his .927 OPS also puts him on pace for a career-high.

Sanó, who Cruz jokingly referred to as his “son,” didn’t mince his words when speaking about his mentor’s accomplishment.

“I hope the Twins can give him a couple more years [on his] contract, and he can retire here,” Sanó said. “I love everything that he taught me this year. Not just me. He teaches [Jonathan Schoop], a lot of players here, too. I want to say thank you, God, for letting me play with Nelson Cruz.”

All that is why teammates Eddie Rosario, Marwin Gonzalez and Sanó were at the top step of the Twins' dugout to be the first to congratulate Cruz once he crossed home plate and pointed to his parents in the crowd. Cruz emerged from the dugout to receive a raucous standing ovation and curtain call in the Twins' regular-season home finale.

The fact that Cruz reached the 400-homer milestone at home meant that he could receive the recognition that he earned throughout the season and, for several moments, had all to himself in the fourth inning, when a crowd of 31,628 at Target Field rose to its feet to salute the leader of the Bomba Squad.

“Maybe he picked the perfect day to do it,” Twins manager Rocco Baldelli said. “It worked out great. We're all honored to be here and witness it and enjoy this experience with him. He's done a lot of great things. This is just the latest one, but it's a very, very special one.”

Cruz will have a chance to soak it all in and truly appreciate the magnitude of his accomplishments at a later date. For now, he just hopes to give that crowd plenty more to cheer about before the Twins close their book on 2019.

"It's definitely something that you really appreciate after the season, because we’re really fighting for something more bigger than that," Cruz said.