"The organization is always looking for what they think is an upgrade, and Billy did some great things for us, but I know we like Eibner," A's manager Bob Melvin said. "He's got some power, looks like he's got a little bit of speed. For us to make this deal, obviously we like the player a lot."
Eibner has 14 home runs this season, 11 with Triple-A Omaha and three over two stints with the Royals -- his most recent ending Friday when he was optioned to Triple-A. In 26 games with Kansas City this year, he hit .231 overall, compared to .288 in 50 Minor League games.
Over parts of three seasons in Triple-A, Eibner is a career .280 hitter with 37 home runs and 140 RBIs in 227 games. He went to the Royals in the second round of the 2010 Draft out of the University of Arkansas.
Burns' departure follows an underwhelming season that came on the heels of an excellent one. As a rookie last year, Burns hit .294 with a .334 on-base percentage and 26 steals to finish fifth in American League Rookie of the Year voting. The performance earned him a spot on the A's Opening Day roster this year, but he was batting just .234 in 73 games at the time of his July 15 demotion.
The A's could potentially find themselves involved in larger deals by Monday's 1 p.m. PT non-waiver Trade Deadline. Left-hander Rich Hill -- who has a blister but could return from the disabled list Thursday -- remains a strong trade candidate, while outfielder Josh Reddick and one of Oakland's relievers could also be moved.
Jane Lee has covered the A's for MLB.com since 2010. Follow her on Twitter @JaneMLB.