With a blade length between 50-60cm, the Gladius was mainly used as a short stabbing weapon. In the heat of battle, Roman soldiers would remain in their blocks, all standing shoulder to shoulder, a huge heavy shield, the Roman scutum, in their left hand, and the Gladius in their right. It was vital for them to stay in formation, and therefore all soldiers were required to fight right-handed (on our courses everyone is asked to fight right-handed as this is more historically correct), and any left-handed soldiers were made to train with their left hand tied behind their back.
The Roman lines would wait until the enemy was almost on top of them before taking a step forward and smashing their shields into their opponents, and when they lost their balance, the Roman soldier would withdraw their shield and stab horizontally with the Gladius aiming to go in-between the ribs and pierce the vital organs. This was almost always fatal. Soldiers were also trained to swipe at the enemies knees from the under the shield whenever the opportunity presented itself.