Mientkiewicz, a former Gold Glove first baseman best known for taking the ball from the final out of Boston's World Series win in 2004, gets a $1.85 million deal with $700,000 in performance bonuses based on games and plate appearances.
Grudzielanek's contract calls for a $4 million salary next season. If he has 500 plate appearances, he gets a $3 million player option for 2007.
The 35-year-old hit .294 with eight home runs and 59 RBI last season in helping the St. Louis Cardinals win the NL Central. He led NL second basemen in fielding percentage (.990) and double plays (108).
"Defensively, I can't say enough good things about Grudzielanek," general manager Allard Baird said. "Mientkiewicz, his defensive ability we feel very good about. We think he's a winner."
"We've added two innings starters, we've added some team speed, we've improved our defense, we've increased our depth in the bullpen," Baird said. "So I feel good about that. But we still have some things left to do. We'll continue to be aggressive."
Mientkiewicz, who turns 31 in June, is a career .268 hitter with 55 home runs and 305 RBI. Bothered by a hamstring injury, he batted .240 with 11 home runs and 29 RBIs in 275 at-bats for the New York Mets last season.
Elarton, 29, gets $4 million annually. He was 11-9 with a 4.61 ERA last season with the Cleveland Indians, making a career-high 31 starts.
Bako, 33, played in 13 games for the Los Angeles Dodgers last year before a knee injury May 26 ended his season. He gets a $700,000, one-year contract.
Baird is looking for a corner outfielder but acknowledged that losing more than 99 games three of the last four years had not helped draw interest in the Royals.
"We've had to reach out," he said. "I've hopped on planes and visited a lot of players, and I think that's the key to this thing. Perception's reality until you know what reality is. The direction of the club -- once you sit down with them, they have a better feel for it. And I think that's put us in the door with a lot more players than if we'd just sat back and said, 'We're offering you this much money to come to Kansas City.'"
Mientkiewicz is in litigation over ownership of the World Series ball with the Red Sox, who filed suit last month asking a judge to let them keep it. The ownership has been in dispute since pitcher Keith Foulke flipped it to Mientkiewicz for the out that gave Boston its first World Series title since 1918.
After he was traded to the New York Mets in January, Mientkiewicz loaned the ball to the Red Sox for one year.
"The Red Sox continue to assert that their former employee, Mientkiewicz, obtained the baseball through the course of his employment, that he acquired no ownership interest and that the Red Sox are the rightful owners of the baseball," the team stated in its suit.