MLB 09: The Show adds features to the previous MLB 08: The Show. The franchise and career modes are improved with Road to the Show 3.0, which updated the mode with a steal and lead-off system, as well as more interaction with the player's coaches. Franchise 2.0 adds several features to its career mode including salary arbitration, waiver transactions, September call-ups, and the 40-man roster. Also receiving an update is the game's online league play, including "Flex scheduling" to allow players to play out-of-order games, and the "Roster Vault" option to allow gamers to create their own custom rosters and upload them online for other gamers to use. The game allows players to store their favorite songs on their PlayStation 3 and assign them to be played at various points in the game. Players may also create custom chants.
Among the in-game improvements include "Hotshot Fielding", which allows more dynamic fielder reactions and animations, as well as improved bare-handed flips, "Progressive Batting Performance", in which player abilities improve or regress depending on how the gamer plays. With "Multi-Branch Fielding", players can now take full control of fielders and break out of any animation in the process, while "Adaptive Pitching Intelligence" (API) allows catchers to call the game based on the individual strengths and weaknesses of each pitcher and analyze tendencies of batters. The game also accurately graphically reflects the pitch being thrown on the pitcher's hand, and includes 18 different pitch types including six fastball variations (four-seamer, two-seamer, running fastball, cutter, splitter, sinker), five breaking pitches (10-4 curve, 12-6 curve, slider, slurve, screwball), four change-ups (straight, circle change-up, palmball, forkball), and three specialty pitches (knuckle, knuckle-curve, and the vulcan changeup). The "Pitch Command System" (PCS) affects a pitcher's ability to throw a specific pitch change depending on how often the pitcher throws it. Umpire personalities have been tweaked further as well.
The game also features pitch analysis, a breakdown of all the pitches thrown during the current game being played, which allows gamers to be able to sort a pitcher by LHB or RHB, pitch type, and result. This feature is also available for batters, and the batter analysis allowed for a breakdown of how a batter had performed based on LHP or RHP, Pitch Type, and result. SportsConnect Online User Tracking (SCOUT) allows gamers to set their game preferences, store them on the server, and then allow the system to look for a Quick Match with an opponent that fits their criteria.
The game also features live MLB updates in-game, as well as SportsConnect Headline News. In addition, SportsConnect provides weekly roster updates that can be downloaded onto the console.