Hayden Panettiere says she's "pretty confident" her baby daddy, Wladimir Klitschko, will destroy Anthony Joshua when they face off later this month ... telling TMZ Sports "we're ready."

Hayden breaks down her role in Klitschko's preparation ... and says she's gonna be right in the front row when it all goes down at Wembley Stadium on April 29.

Should be a good one.