It all depends I say; meaning the battle can go either way. Gaara's skills and abilities with his Sand Techniques has improved, along with his intelligence, on and off the battlefield, since the time-skip. He also has many advantages, versatile range with his sand (e.g. Close, Med, and Far) that can prove to be a disadvantage to Minato's placing of FTG and geographical, in which can turn the terrain into sand. However, you comparing Part 1 Speed of Sasuke breaking a Part 1 barrier made by Gaara it is high unlikely the same thing can happen between Minato and Gaara fight. Minato can still throw FTG (FTG Level 2), however, which is still a low successful-rate at making it's mark because Gaara's Sand is unpredictable at times.