Here, I'll do the math for you.
Ogre: AC 15, 32 HP, +4 to hit, 2d8+4 Bludgeoning Damage
5th-Level Fighter: AC 18 (Banded + Shield); 44 HP (+2 Con), +7 to hit (+4 Fighter, +3 Strength), 1d8+3 damage (Longsword, +3 Str), 2d8 Expertise Dice
Assuming the Fighter uses no combat maneuvers at all...