Sasuke is capable of winning but only with extremely high difficulty and the fight will tie many times in Minato's favor due to the fact that Minato could use Shiki Fujin or simply run away. If Minato tags Sasuke, the fight ends instantly in Sasuke's defeat, but with Susano'o that won't be happening easily. Nothing bar Shiki Fujin will hurt Sasuke thanks to Susano'o, and that will require Minato's own life, plus Susano'o might end up hurting Minato if he tries a close quarters fight Sasuke thanks to the flaming Susano'o with black flames.
Unless Minato intends to kill Sasuke by throwing him off some high place, his contract seal will be useless and considering the location, that is not happening. Sasuke with Sharingan's photographic memory will memorize where all the FTG kunai's land and nothing is stopping him from burning them all, or even burning them mid flight. If Minato summon's Bunta, he will simply get genjutsu controlled or Ama'd by Sasuke. If Minato uses Food Cart Destroyer, Susano'o will tank it, and then Bunta goes under Sharingan control or gets Ama'd.
Then there is the matter of Sasuke's genjutsu. Minato has no genjutsu feats or feats of breaking them, though he is intelligent enough to notice all but the most subtle genjutsu. He isn't as stupid as Danzo either, not by a long shot so fooling Minato will be troublesome, if he can do it all. Then there is the fact that Minato most likely knows not to look a Sharingan user in the eye. Sasuke's paralysis genjutsu could open the door for a win, but like I said, Minato is not looking him in the eye, so that won't happen frequently. I haven't even account to the variable outcomes due to luck, unknown abilities, and Minato's gorgeous mind.
In the end, out of ten times, I see Sasuke winning 3 thanks to burning the markings and controlling Minato's summons, Minato winning 2, and the rest of the time a draw in Minato's favor thanks to being able to warp to a safehouse, or using Shiki Fujin.