Jedd Fisch is in love with, obsessed by and working bleary-eyed hours in a sport he never played.

Ever.

At any level.

But that's OK with a guy like John Carlson, who was all-state at Litchfield High School and a two-time captain at Notre Dame and is now a tight end for the Seattle Seahawks.

"You know," Carlson said, "the fact he has that love and passion without ever playing is pretty cool, I think."

Of course, Carlson is biased since it was with Fisch's help that Carlson played a starring role in a game plan that helped the Seahawks upset the defending Super Bowl champion Saints 41-36 and shock the world in last week's wild-card playoff game.

Fisch -- the former Gophers offensive coordinator, current Seahawks quarterbacks coach and recently hired offensive coordinator at Miami (Fla.) -- was studying film of the Saints red-zone defense two weeks ago when he saw something that piqued his interest. In the Cincinnati game from Week 13, the Bengals ran the ball to the right as the backside tight end went to the ground on a cut block. Fisch noticed that New Orleans paid no attention to the tight end once he got back up during the play.

"The safety to that side [Roman Harper] actually forgot about the tight end," Carlson said. "Our coaches told me, 'If you throw a cut block and you're patient with it, you should be wide open.' And they were right."

The Saints were leading 17-7 early in the second quarter when Seattle reached the New Orleans 7-yard line. That's when offensive coordinator Jeremy Bates called the play Fisch helped design. Lined up on the left side, Carlson dived at the feet of Harper and stayed on the ground briefly as quarterback Matt Hasselbeck sold a run fake to the right.

Harper moved toward Hasselbeck, completely unaware that Carlson was now back on his feet behind him. Hasselbeck turned and threw the easy touchdown pass. It was Carlson's second touchdown of the game, which doubled his regular-season total heading into Sunday's divisional playoff game between the visiting Seahawks (8-9) and the No. 2-seeded Bears (11-5).

"Never went to the ground, laid there, got back up and caught a touchdown pass in my career," Carlson said. "Not at any level."

Consider it just another step in a coaching career that Fisch, 34, describes as having followed "kind of a weird path."

Fisch's obsession began when he was a 10-year-old ballboy for the perennial state champion Bergen Catholic High School team in his northern New Jersey hometown of Livingston. His mother was dating the coach, who became a mentor to Fisch.

Fisch never played football because he was an elite youth tennis player who ended up moving to the Nick Bollettieri Tennis Academy in Bradenton, Fla. He went on to the University of Florida, but not because of tennis.

"If I was going to follow my passion for coaching, I needed to pick the school that had the best football coach in the country," Fisch said. "And at the time, that was Steve Spurrier."

Spurrier wouldn't give Fisch the time of day at first. So Fisch went to nearby P.K. Yonge High School in Gainesville to volunteer as an assistant coach. Eventually, his path crossed with a Gators assistant coach who recruited the area. The assistant recommended to Spurrier that he hire Fisch as a graduate assistant, and a career took off.

Fisch was 24 when he was hired by Dom Capers to help build the expansion Houston Texans from the ground up in 2001. He was 26 in 2003 when he nearly died from aortic aneurysm, which only drove him to work harder.

Since then, he has worked under Brian Billick in Baltimore, Mike Shanahan in Denver and Pete Carroll in Seattle. Fisch admits having no playing experience "was a path I had to overcome as a coach." But he did because he said this is all he's ever really wanted to do with his life.

"Coach Fisch proves every day he knows what he's talking about," Carlson said. "And you can't put in the ridiculous hours coaches put in if you don't have the love and passion. In practice, the meeting room and on game day, he's always proving he belongs."

Mark Craig • mcraig@startribune.com