Mana leak

[Drbusta50]

I just got thrown for a loop.  Scenario- I play a {sun Titan} I pay the required mana of 6.  I have two remaining lands, my opponent plays a {mana leak} so obviously the Titan is countered.  He then tells me I need to tap my remaining lands to account for the 3 mana to prevent the leak.  My question is if some plays a {mana leak} I can choose not to pay the 3 mana and let it resolve right.  And even so if I cant pay the mana I shouldn't need to tap my remaining mana

[BlackJester]

Whoa!  No, no, no.  You can either chose to pay the full amount (3) or let the spell be countered.  No partial payments are possible or expected.  He's probably thinking along the lines of {Power Sink} or something. (Or trying to be shifty, no way for me to know).