Roman Legion or Macedonian Phalanx?

Equal numbers, who wins?

Also, leave generalship aside. A good middling officer leads both.

The more mobile legions would win.

The phalanx isn't used in exclusion to anything else. You need cavalry and general infantry to keep the phalanx from getting flanked. Once they're flanked, they're 100% FUCKED because their weapons (20 ft spears) are useless at close range.

Unless they're fighting the Assyrians, who had lightweight, horse-drawn chariots. :-)

and certainly when they had competent generals. History is full of battles as the Romans were expanding east that this was tested.

The legionaries hurl their pila at the shields of the phalanx soldiers. They either stick in the shields and bend at the shank, making the shields useless, or they miss the shields, hit the ground and break on impact, making the pila themselves useless for "hurl-back". Many phalanx soldiers now have no shields. Each legionary hurls his second spear, disabling more shields and killing phalanx soldiers. The legionaries draw their gladii short swords and advance to within thrusting range of the remaining phalanx spears. Using their vaunted teamwork, the legionaries smash the spears up and out of the way, leaving each phalanx soldier vulnerable to a sword thrust from each legionary's mate. After that, a tough, hand-to-hand slog, but the legionaries will carry the day.