Yup...I said it. And so did the manga in so many ways. Not saying gaara is overall stronget than minato, but gaara is a bad match up for him.
1. Gaara can fly. Minato can't. He has no ranged jutsu that gaara would even consider a threat.
He's not marking him. Let's be realistic. And I'll tell you exactly why he's not<
2. Sand shuriken. With gaara flying, minato would have to throw his kunai, which mind you, is a regular kunai...nothing special about it but the paper seal on it, can simply be intercepted by sand shuriken. This ours minato at a extreme disadvantage because:
3. Gaara can simultaneously attack and defend.
If minato doesn't mark a ftg spot far from the battlefield, he's dead...I'll explain< if gaara decides to do sand tsunami and change the landscape to that of a desert, even if minato throws a kunai, it won't travel far enough in time to outrun this massive wall of sand.
4. People say gaara needs a location advantage in certain fights. Guess what? Pts gaara turned a forest into a desert in a instant while constantly making his own sand. He can make any location homefield.
Sorry...but minato takes an L pretty badly.