When the current Collective Bargaining Agreement radically revamped the First-Year Player Draft rules, the action surrounding the annual signing deadline diminished considerably.

Under the last Draft under the old CBA in 2011, when Major League Baseball dissuaded teams from announcing lavish deals in advance of the deadline, 22 first-rounders signed on the final day and teams paid out a total of $139.1 million in bonuses and guaranteed money to 101 players. Contrast that to the first two deadline days under the current CBA, which have averaged two first-round signings and $14.7 million in total spending on 21 signees.

There's more drama in advance of Friday's 5 p.m. ET signing deadline, however. While there are only three first-rounders among 11 players in the first 10 rounds who remain unsigned as of early Thursday evening, No. 1 overall choice Brady Aiken headlines them.

A left-hander from Cathedral Catholic High (San Diego), Aiken agreed to terms on a $6.5 million bonus on June 7, two days after the Astros selected him. But a physical on June 23 made Houston concerned about his left elbow. The Astros subsequently offered Aiken $3,168,840, which equals the minimum 40 percent of his assigned pick value ($7,922,100) required to receive the No. 2 overall choice in 2015 as compensation if he doesn't sign.

Casey Close of Excel Sports Management, who's advising Aiken, has accused Houston of trying to manipulate its Draft pool to reduce Aiken's bonus and create extra money to sign 21st-round pick Mac Marshall, a Parkview (Ga.) High left-hander who was considered a top-three-rounds talent. Caught in the crossfire is fifth-rounder Jacob Nix, a Los Alamitos (Calif.) High righty who agreed to a $1.5 million bonus within two weeks of the Draft. Nix, who's also advised by Close and Excel, had his deal put on hold because if the Astros paid him $1.5 million and didn't sign Aiken, they would exceed their bonus pool by more than 15 percent -- and forfeit their next two first-round picks as a penalty under the Draft rules.