Aoki, 31, a left-handed hitter from Japan, is expected to take over the leadoff spot in the Royals' lineup so that left fielder Alex Gordon can move permanently into the middle of the order. Aoki was the Brewers' right fielder, which is Beltran's position.
However, general manager Dayton Moore, who met with Beltran at Kauffman Stadium for most of the day on Tuesday, indicated the pursuit of the prized free agent isn't over because of the Aoki acquisition.
"This really is a move that we think puts us in a position to have a true leadoff hitter, allows Gordo to perform in the middle of the order and the offseason still remains very fluid," Moore said. "We're going to continue to pursue talent to improve our team prior to Opening Day."
More immediately, that means next week during the Winter Meetings in Lake Buena Vista, Fla.
This is the Royals' second big move of the offseason. Earlier, they signed left-handed pitcher Jason Vargas to a four-year, $32 million contract.
The Royals will have Aoki under control for just the 2014 season, after which he will become a free agent despite having just three years of Major League service time. His original contract with the Brewers -- as is customary with players signed out of Japan -- stipulated he would become an untethered free agent when it expired. But he comes to the Royals at a relative bargain, $1.95 million for the year.
Primarily in the No. 1 spot in the Brewers' order last season, Aoki hit .286, scored 80 runs and had eight homers, 37 RBIs and 20 stolen bases in 32 attempts. His on-base percentage was .356 and he ranked second in the Major Leagues with 40 infield hits and led the National League in singles, with 140.
"With Nori at the top of the lineup, putting pressure on the defense and getting on base certainly improves our offense," Moore said. "In our minds, he can score 100 runs."
Aoki didn't strike out much (just 40 times in 674 plate appearances) and hit left-handed pitchers better than any left-handed batter in the Majors, .339 (60-for-181).
Dale Sveum, the new Royals third-base coach and former Cubs manager, saw a lot of Aoki in the NL Central the last two seasons.
"[Sveum] likes him as a leadoff hitter and likes his ability to play right, but feels like he can play center as well," Moore said. "But the most important thing he does for us is he sets up our lineup to lead off and get on base, put the ball in play and steal bases. We think his success ratio on stolen bases can improve. We like his energy, we like his work ethic."
If Beltran were to sign with the Royals, the team is comfortable that Aoki could play center field, his primary position in eight seasons with the Tokyo Yakult Swallows in Japan.
"We like him as above-average in right field and feel like he can play center. His routes are very good, he plays pretty deep but he comes in on the ball very well, and we think that he has enough athleticism and experience to play center field," Moore said. "[His arm has a] quick release, on target, actually better than it appears when you watch him throw live. It plays up during the game and he's a smart, instinctive player."
Lorenzo Cain, one of five Royals nominated for a Gold Glove Award this year, is the incumbent center fielder. Just what this deal will mean for him and other outfielders such as David Lough, Justin Maxwell and Jarrod Dyson likely will hinge on any future moves, most prominently where Beltran ends up.
Smith, 24, is expected to compete for a starting job with the Brewers. As a Royals rookie in 2012, he made 16 starts, posting a 6-9 record and a 5.32 ERA. But he spent most of last season in the bullpen after being moved from a starting role at Triple-A Omaha. For Kansas City, he was 2-1 with a 3.24 ERA in 19 games, including one start.
"I love a lot of things about Will," Moore said. "He's very competitive, he's very poised, he's got a lot of toughness, I think he's got the ability to start at the big league level. He was certainly very impactful for us last year as a reliever. All these deals come with a cost. You have to give up quality talent to obtain quality talent. We don't have a ton of depth with left-handed pitching, but we do have some. You never have enough, but we felt this was a move we had to make to improve our team."
In addition to Vargas, the Royals also have potential left-handed starters in Danny Duffy, Chris Dwyer and Everett Teaford.
Smith was obtained by the Royals in midseason 2010 from the Angels with right-hander Sean O'Sullivan in a trade for third baseman Alberto Callaspo.
Before signing a two-year contract with Milwaukee, Aoki's eight seasons in Japan resulted in a career average of .329 and three batting titles.
His departure means that Ryan Braun, returning from his suspension, will move from left field to right for the Brewers.
Aoki will be the first Japanese-born position player on the Royals' roster. The previous three players from that country were pitchers -- Mac Suzuki (1999-2002), Yasuhiko Yabuta (2008-09) and Hideo Nomo ('08).
"I have a tremendous amount of respect for the Japanese talent and Japanese players," Moore said. "They're fundamentally sound, they're very prepared, they're smart, they love to play and we're proud to have Nori as a part of the organization."
Meantime, the Beltran situation remains in limbo.
"There's really nothing I can say about that. ... I can't control what other players decide," Moore said. "We've just got to continue to move forward and build our team, and that's what we've done today."