singed broken?

ok so i was playing and my team faced a singed. typical build, , , , , , . so we started a fight mid lane all of a sudden (not using TP) singed ults, pops and all a sudden his movement speed is up around 700, i mean my team had no time to react and was overwhelmed by the speed at which he moved, not to mention the amount of damage he did to me, jinx. now i dont want to say the guy cheated, but ive never seen someone with move speed that high except for a Heca coming off a homeguard tp with ghost, and even then it decayed very fast, his didnt, he was able to make it from about middle of mid lane to in between t1-t2 towers, with 0 MS loss. please look into this, i tried and couldnt make singed move that fast without a base tp.