In November 2009, Don Atchison (RBI/Mayo 12U manager, AACBL) had several 11 year olds turning 12. Chesapeake Legends 12U (CBA) also had several 11 year olds turning 12. Don contacted Legends manager Mike Graham and Coach Chris Cummings about merging their teams for Spring 2010. 

A combined workout was held in December 2009 which went well, and Don, Mike and Chris merged the teams to play as one team in 2010. Don was the manager/head coach and former collegiate player Chris assistant coach. Former pro baseball player Coach Ken Arnold (PAL Astros 12U) contacted Don and brought with him several 11 year olds turning 12.

The amalgamation of primarily former RBI/Mayo, Legends and PAL players went forward as the RBI Angels 12U. They played in the AACBL "A" division and went 13-5 (.722) and finished in second place.

In August 2010, open tryouts were announced to fill several vacated spots and 21 players answered the call. The staff selected 14 players to play in the 14U Stuart Schmidt Fall League. They went 6-1-1. After the fall, Don's real life job required him to step down as manager and was replaced by Mike as manager. Ken and Chris continued as the coaches.

In December 2010, open tryouts were announced for the spring to fill several vacated spots on the roster after the fall campaign and 2 players were selected for a 13-player spring roster. The team worked out indoors December-February.

In Spring 2011, as RBI 13U the team's schedule included playing regular season in the Chesapeake Baseball Association and these tournaments: Annapolis Open, Upper Chesapeake Festival, Maryland Stars May Day Classic, Walk the Plank, and CBA States. Overall the team played 48 games, going 29-19 (.604) in spring ball.

In Summer 2011, three 13-year old players from RBI's AACBL 14UA team were added to fill several vacated spots for a 12-player summer roster. The team's schedule included "playing up" in the AAC Summer Classic, LFYAA Invitational, Gambrills Roundrobin, Nations Mid-Atlantic States Regional, HCYP Invitational, and Virginia Dog Days of Summer tournaments. The team played 24 games, going 13-11 (.542) in summer tournament ball with 1 championship, 2 second places, and one third place. In all, the team played 77 games (47-29-1, .617) during the 2010-2011 season.

In August 2011, open tryouts were announced and 22 players answered the call, including 9 returners. The staff selected 14 players to play a fall schedule of pick-up and league games and tournaments.

As RBI 14U the team's Fall 2011 schedule included playing regular season in the Southern Maryland Travel League, Southern Maryland Fall Classic Tournament, and pick up games through the Annapolis Area Fall Travel League. Overall the team played 18 games (5-13, .278).

With half the players in 8th grade and half freshmen, the team's Spring 2012 season included 28 games (22-5-1, .804), winning the RBI Freshman 13-15 Wood Bat League, RBI Freshman 13-15 Wood Bat Tournament, and finishing 3rd in the Memorial Day Goodwill Games 16U group.

In Summer 2012, the team played 40 games in the RBI High School Eligible JV 16U Wood Bat League, some tournaments, and pick up games. The schedule included playing in the Attackers Invitational, LFYAA Invitational, Virginia Dog Days of Summer, and RBI JV Wood Bat tournaments. The team went 29-11 with 2 tournament championships and 2 second places. In all, the team played 86 games (56-29-1, .657) during the 2011-2012 season.

In August 2012, open tryouts were announced and 27 players answered the call, including 9 returners. The staff selected 12 players and played 21 games in the RBI High School Eligible Fall JV 16U Wood Bat League, going 18-3 (.857) and winning the league and tournament championship. 

In 2013 the team went 24-23 (.511) after the high school season in the Spring/Summer  RBI High School Eligible Varsity 19U Wood Bat League, tournaments, and pick-up games. RBI received invitation and represented the Mid-Atlantic Region in the AAU Underclassmen Super Showcase National Championship in Florida. In all, Maryland RBI played 68 games (42-26, .617) during the 2012-2013 season.

During Fall 2013, Maryland RBI played in the fall RBI AAU High School Eligible Varsity 19U Wood Bat League, going 11-2 (.846) and winning the AAU Maryland Fall Wood Bat State Championship. In the winter, the team did indoor workouts. 

After the Spring 2014 high school season, Maryland RBI, still a true 17U team, played 36 games (15-21, .416)  in the Spring/Summer  19U and 23U high school/college wood bat league, tournaments, and pick-up games against teams from Maryland, Virginia, and Washington, DC.

In Fall 2014, Maryland RBI went 12-0-2 in the RBI AAU High School Eligible Varsity 19U Wood Bat League repeating as the AAU Maryland Fall Wood Bat State Champions. In the Spring/Summer 2015 season, the team played in the AAU 19U Mid-Atlantic Wood Bat League and Washington Nationals Youth Baseball Academy/DC Metro League (19-9-4).

In Spring/Summer 2016, Maryland RBI went 11-9 in the AAU 19U Mid-Atlantic Wood Bat League, winning the regular season championship but losing in the tournament championship game. An astounding nine current players and alumni and three coaches advanced to the collegiate summer baseball leagues.

In Spring/Summer 2017, Maryland RBI went undefeated (18-0) in the AAU 19U Mid-Atlantic Wood Bat League, winning both the regular season and tournament championships. Ten current players and alumni and two coaches proceeded to the collegiate summer baseball leagues.

Since Spring 2010, Maryland RBI has logged over 2,000 hours of advanced skills development baseball together playing over 300 games, training, and attending camps and clinics.