After the First Battle of İnönü, where Miralay (Colonel) İsmet Bey fought against a Greek detachment out of occupied Bursa, the Greeks prepared for another attack aiming the towns of Eskisehir and Afyonkarahisar with their inter-connecting rail-lines. Ptolemaios Sarigiannis, staff officer in the Army of Asia Minor, made the offensive plan.

The Greeks were determined to make up for the setback they suffered in January and prepared a much larger force, outnumbering Mirliva İsmet's (a Pasha now) troops. The Greeks had grouped their forces in Bursa, Uşak, İzmit and Gebze. Against them, the Turks had grouped their forces at northwest of Eskişehir, east of Dumlupınar and Kocaeli.

The battle began with a Greek assault on the positions of İsmet's troops on March 23, 1921. It took them four days to reach İnönü due to delaying action of the Turkish front. The better-equipped Greeks pushed back the Turks and took the dominant hill called Metristepe on the 27th. A night counter-attack by the Turks failed to recapture it. Meanwhile, on March 24, Greek I Army Corps took Kara Hisâr-ı Sâhib (present-day Afyonkarahisar) after running over Dumlupınar positions. On 31 March İsmet attacked again after receiving reinforcements, and recaptured Metristepe. In a continuation battle in April, Refet Pasha retook the town of Kara Hisâr. The Greek III Army Corps retreated.

This battle marked a turning point in the war. This was the first time the newly formed Turkish standing army faced their enemy and proved themselves to be a serious and well led force, not just a collection of rebels. This was a very much needed success for Mustafa Kemal Pasha, as his opponents in Ankara were questioning his delay and failure in countering the rapid Greek advances in Anatolia. This battle forced the Allied capitals to take note of the Ankara Government and eventually within the same month they ended up sending their representatives there for talks. France and Italy changed their positions and became supportive of Ankara government in short order.