In 2245, at the onset of the Earth-Minbari War the Lexington was under the command of Captain Roger Sterns, with Commander John Sheridan as his first officer. The Lexington was considered an old patrol ship.
In 2247, in the aftermath of the initial Minbari advance, the Lexington was at Earth undergoing a refit. The Lexington led a small task force on a patrol. The Lexington was ambushed by Minbari warships and Captain Sterns was killed. With the Lexington crippled from the ambush, Sheridan used nuclear warheads to mine an asteroid field and succeeded in destroying a Minbari flagship, the Black Star. 
Though the Lexington survived the encounter, it suffered extensive damage and would spend some time being repaired.
|Earthforce Ship Classes|
|Olympus-class corvette Hyperion-class heavy cruiser Nova-class dreadnought Omega-class destroyer Advanced Omega-class destroyer Warlock-class destroyer|
|SA-23E Starfury SA-32A Thunderbolt Stealth Starfury Heavy Starfury Badger-class Starfury|
|Earthforce One Magnum heavy lifter Breaching pod Troop Transport Kestrel Class Atmospheric Shuttle Crew Shuttle|
|Aegis orbital defense platform Life pod Work pod Gunship Explorer class ship Cotten class Deep Penetration Tender Shadow Hybrid|
|Hyperion Class Heavy Cruisers|
|EAS Amundsen EAS Aegean EAS Clarkstown EAS Hyperion EAS Lexington EAS Prometheus EAS Trafalgar|