Minato fought to eliminate Tobi, he trusted Hiruzen to protect Konoha.
Tobi was fighting with his time limit on Kurama in mind too.
Tobi has a decent chance because he lost due to not knowing one detail; if he had knowledge then he would have remained intangible for a bit longer then grabbed Minato right after he used Rasengan on the ground.
I saw how close it was, tobi was practically tocuhing minato and how much did minato know about tobi?
Tobi saw minato use SBT, FTG, and minato was a well known legend Tobi was no one yet still minato released karuma from tobi while dealing a critical blow, then he dealt another.
That fight was pretty one sided IMO.
Lets not forget even after that he had enough chakra to teleport a fully sized karuma and his bijuu bomb, then seal the other half in naruto.