RBI Baseball was licensed by the Major League Baseball Players Association (MLBPA) and used actual MLB player names, unlike other baseball video games of the late 1980s. It was not licensed by Major League Baseball (MLB) itself, however, and thus did not use team nicknames or logos. Instead, the game contained 8 teams listed only by city name: Boston, California, Detroit, Houston, Minnesota, New York, St. Louis, and San Francisco; their real-life, MLB counterparts were the playoff teams in the 1986 (Boston, California, Houston, New York) and 1987 (Detroit, Minnesota, St. Louis, San Francisco) MLB seasons. The game also boasted two All-Star teams, American League and National League; the two featured established veterans such as George Brett, Dale Murphy and Andre Dawson—none of whom appeared on the other eight teams—and up-and-coming players like Mark McGwire, Andrés Galarraga and José Canseco.
Each player has different capabilities in the game; hitters vary in ability to make solid contact, to hit the ball with power, and their base running speed. Vince Coleman is the fastest player in the game; it is very difficult to catch him stealing second base. Pitchers vary in pitching speed, and the amount by which the player can steer the ball left and right during its flight. Pitchers also have varying stamina; as a pitcher gets tired, the ball slows down and is harder to steer. Nolan Ryan and Roger Clemens are two pitchers in the game with the fastest pitches. Fernando Valenzuela, without a hard fastball, has tremendous movement in both directions with his pitches. Mike Scott has a sharp and deceptive breaking ball. The best pitcher is debatable, depending on how they are used by the players. There is no evidence that fielding abilities correspond to individual players.
The abilities of each player do not necessary correspond with the statistics shown on the screen when the player comes to bat or takes the mound. These statistics are generally accurate, with many exceptions (see below). They do not change during the course of the game or sequence of games.
A rudimentary box score is displayed during and after the game showing composite statistics for each team. A hit batter is credited with a walk, and anyone reaching on an error gets credited for a hit even as the other team is charged with an error. Conversely, a batter thrown out while trying for extra bases is not credited with a hit.
The rosters for the 8 teams are fairly accurate if simplified representations of the playoff rosters from their respective years. Each team has 8 starting batters, four bench players, two starting pitchers and two relievers. The player can start any pitcher they like, though the relievers have very low stamina. But if they play consecutive games without resetting the system, any starting pitcher used in the previous game will be unavailable. The player has to wait until the game starts before substituting players with pinch hitters, who can play any position.
In Vs. RBI Baseball, the teams are made up of legends from 10 different franchises. These players were statistically represented with their best seasons. A notable exception was that of McGwire, who was included on the Oakland team, and was statistically represented by his potential numbers. In a remarkable display of foresight, he was projected to hit 62 home runs in his best season. In 1998, he set the major league record for home runs in a season with 70.
Source: Wikipedia, "Rbi baseball", available under the CC-BY-SA License.