Santa Clara, Calif. ? Coach Dennis Erickson and general manager Terry Donahue presided over some of the darkest days in the proud history of the San Francisco 49ers, who lost games, good players and incalculable respect in recent years.

They insisted they had a plan to restore the franchise to glory, but owner John York decided it was time for a whole new plan.

York fired Erickson and dismissed Donahue on Wednesday, just three days after the 49ers finished with the NFL’s worst record. York made a rare public appearance to announce the dramatic changes to his team, which went 2-14 to match the worst season in San Francisco history.

“Sometimes, even when everyone works very hard, the formula for winning just isn’t there,” York said. “We’re going to use the extreme disappointment that we all have felt as our turning point.

“We know how much passion 49ers fans have, and we understand that this is unacceptable to our fans. We need our fans to know that it is equally unacceptable to us. We take our responsibility as owners seriously.”

Erickson went 9-23 in two seasons as Steve Mariucci’s successor, never reaching the postseason. He won two national championships at the University of Miami during a successful college coaching career, but is 40-56 in six seasons as an NFL coach in San Francisco and Seattle.

Erickson had three years and $7.5 million remaining on the contract he signed in 2003.

The hefty financial package was thought to be the biggest obstacle to York’s desire to make changes, but the owner decided to shoulder the expense — in total, paying Erickson about $1.39 million for every victory with the 49ers.