Adelaide has claimed a thrilling Showdown by one point after Brayden Cook nailed a game-winning goal with 10 seconds remaining.Cook's heroics gave Adelaide a 11.10 (76) to 11.9 (75) win over cross-town rivals Port Adelaide in a match which saw the two sides exchange leads inside the final minute.After leading by as many as 21 points early in the final quarter, Adelaide found itself trailing with 46 seconds left when Port's Joe Berry nailed a left-footed snap out of congestion.Crows star Izak Rankine won a free kick shortly after the ensuing centre bounce and after he sent the ball forward, Dan Curtin found Cook with a handball, before Cook drilled the goal from an acute angle on the run from 45m out."I have no idea, everything is just spinning," Cook told Fox Footy when asked what's going through his head after his match-winner."I can't even talk Clutch."It [the second-last centre bounce] didn't go to plan, but Ranks won the free kick."ADELAIDE WINS IT RIGHT AT THE DEATH! WHAT A BLOODY SHOWDOWN! THE GOAT SHOWDOWN MAYBE? I'M CALLING IT!Absolutely unbelievable scenes here at the Adelaide Oval as the final siren sounds.Port thought they'd won it, Adelaide thought they'd won it, then Port thought they'd won it again, and then Adelaide finally won it.Holy smokes