Flash can dodge most of what wonderman has to offer and if the fight goes on long enough I think he'll ramp up his game enough to put him down. Even if he doesnt immediately begin pummeling him down, in character Flash should do his absolute top notch perception wise to dodge attacks and a well written Flash's perception and ability to actively react should mean that Wonderman should maybe land 1 or 2 hits if Flash is cocky. But once he gets serious Wonderman shouldn't touch him again and from their its a matter of escalation of the Flash's part to eventually put him down.