Todd Therrien says he's starting his head coaching career with a minus.

"I've already broken the first rule of coaching," he says with a chuckle. "Never follow a legend."

Therrien, a Seraphs assistant for the past eight seasons, assumed formidable reins Tuesday when he was named the successor to Jon Mack and the interim head coach of the St. Bonaventure High football team.

Mack, also the Seraphs' athletic director, and Principal Brother Paulinus Horkan made the decision after meeting Tuesday.

"His commitment, his dedication made him the choice," said Horkan.

The St. Bonaventure High principal, who is retiring from his position in June, said the next principal will likely remove "interim" from Therrien's job title.

Mack last week became the head football coach at Ventura College after 17 seasons in which he transformed St. Bonaventure into a county and Southern California powerhouse.

Mack's teams won seven CIF-Southern Section championships, notched a 43-game winning streak and piled up a record of 163-47-1. The Seraphs won back-to-back Division IV championships in 2004 and 2005.

Therrien was with Mack for 15 of those 17 seasons as a player and coach. He is the program's longtime defensive coordinator.

"I'm excited, and a little sad," said Therrien, a graduate of St. Bonaventure High and Ventura College. "I'm excited for the opportunity, but I'm sad that I won't be with Jon Mack."

Therrien, at age 28, becomes one of the region's youngest head football coaches.

"That might seem young in years, but I'm ready for the opportunity," he said. "I've spent the last eight years preparing for the challenge."

Therrien said he cut his coaching teeth "sleeping on Jon Mack's couch."

He vows to continue the winning tradition.

"The program will look exactly the same," he said. "Nothing is going to change. We're never going to lose a game because of lack of preparation."

Therrien expects to retain his duties as defensive coordinator, at least for the 2007 season. He also expects the "majority" of the current coaching staff to remain on board.

Therrien, who is married to wife Christina, joined the St. Bonaventure coaching staff in 1998. As a player, he has the distinction to be the last of a breed in the program.

"I was the last player to start both ways," he said. "I started at middle linebacker and at right guard."

He inherits another talented roster next season that includes offensive lineman Vaughan Dotsy, linebacker Ryan Panapa and running back Darrell Scott, a transfer from Moorpark High.

"We'll have a great senior class, and we've got strong classes below them as well," he said.