{"numbering":"asc","slides":[{"index":1,"title":"Choices to make","image":"https://www.nbcsports.com/sites/rsnunited/files/archive/assets_media_gallery/bayarea/2015/08/27/melvin-bob-upi.jpg","caption":"

Most of the A’s top-rated prospects are in the lower levels of the minors, and therefore not yet ready for a September call-up. But the following is a look at some of the more intriguing players who could get promoted sometime after major league rosters expand Sept. 1... ----Joe Stiglich

"},{"index":3,"title":"RHP Aaron Brooks","image":"https://www.nbcsports.com/sites/rsnunited/files/archive/assets_media_gallery/bayarea/2015/08/27/brooks-aaron-usa.jpg","caption":"

With the recent injuries to hit the A’s rotation, they’re in need of starting depth. Brooks can provide it. He was sharp in his first two starts after coming over from Kansas City in the Ben Zobrist trade, then he got roughed up against Toronto and gave up a walk-off homer in relief against Baltimore before being optioned to Triple-A Nashville. Giving Brooks, 25, some more big league exposure would provide the A’s a better read on whether he’s ready to compete for the 2016 rotation.

"},{"index":5,"title":"INF Tyler Ladendorf","image":"https://www.nbcsports.com/sites/rsnunited/files/archive/assets_media_gallery/bayarea/2015/08/27/ladendorf-tyler-usa.jpg","caption":"

The versatile Ladendorf enjoyed an excellent spring training that won him a spot on the Opening Night roster. After being optioned to Nashville, he fractured his ankle in April and missed roughly four months while recovering from surgery. A late bloomer in the minors, Ladendorf, 27, can play anywhere in the infield as well as the corner outfield spots. He should contend for a roster spot again next spring. Unlike second baseman Joey Wendle, another infielder at Nashville that fans are curious about, Ladendorf is already on the 40-man roster, making it easier to promote him.

"},{"index":7,"title":"LHP Sean Nolin","image":"https://www.nbcsports.com/sites/rsnunited/files/archive/assets_media_gallery/bayarea/2015/08/27/nolin-sean-usa.jpg","caption":"

Acquired last winter in the Josh Donaldson trade, Nolin’s season has been sabotaged by injuries – first from complications stemming from sports hernia surgery, and more recently a shoulder injury. He’s healthy now, and even though he’s still building up his innings, it stands to reason that A’s officials might want to see what this 25-year-old lefty can do on the big stage, even if it’s in relief.

"},{"index":9,"title":"1B Rangel Ravelo","image":"https://www.nbcsports.com/sites/rsnunited/files/archive/assets_media_gallery/bayarea/2015/08/27/ravel-rangel-usa.jpg","caption":"

Another player acquired via trade last offseason, Ravelo was viewed as having the potential to impact the big league club in 2015. But he suffered a wrist injury in spring training that required surgery and missed a large chunk of time. Leading into Wednesday, the 23-year-old Ravelo was hitting .322 overall through 47 games spread at three different levels. He’s currently playing first base for Nashville, but the A’s view him as perhaps having the tools to handle third base too.

"},{"index":11,"title":"RHP R.J. Alvarez","image":"https://www.nbcsports.com/sites/rsnunited/files/archive/assets_media_gallery/bayarea/2015/08/27/alvarez-rj-usa.jpg","caption":"

This hard-throwing reliever is a known quantity to A’s fans, as he’s had multiple stints with the big league club this season. It makes sense that he could get another call-up come September. Alvarez, 24, has big-time stuff, and that makes him a potential factor to open up 2016 in the major league bullpen.

"}]}

A's September call-up candidates