New York Jets assistant Greg Knapp, a well-traveled NFL coach who worked with Pro Football Hall of Famer Steve Young and soon-to-be-inducted Peyton Manning over his 25-year career, died Thursday from injuries suffered when he was struck by a car while biking Saturday in San Ramon, California. He was 58.

The affable Knapp, known for his expertise with quarterbacks, was only days away from flying to New Jersey to begin his first season as the Jets' passing-game specialist under new coach Robert Saleh. The Jets' rookies reported to training camp Tuesday.

"Greg had such an inner peace about him that people always seemed to gravitate towards," Saleh said in a statement posted to Twitter. "He lived life in a loving way that helped him connect with people from all walks of life in a unique way.

"In his short time here, I believe the people in this organization had a chance to experience that connection. Greg, thank you for all that you have shared with us, you will be missed brother."

Hired in January, Knapp made "genuine connections with all of our coaches, players and staff," said Saleh, who described him as having "a fun nature, kind disposition, and (a) wealth of knowledge."

An avid bicyclist, Knapp was hit by a single motorist at about 2:49 p.m., not far from his home in Danville, San Ramon police said. The driver of the vehicle, whose name is being withheld, wasn't under the influence of drugs or alcohol and is cooperating with the ongoing investigation, according to police.

"Those of us who were so blessed to have known him, know that he would have wanted even this moment to be a teachable one," the family said in a statement. "So this is it...'Live every day as if it's your last, and love those around you like it won't last!'

The family said in the statement that Knapp died at 2:32 p.m. ET, five days after being struck. He never regained consciousness.

He was surrounded by his mother, wife, three daughters and his brother when he died.

"Greg's infectious personality is most people's first and lasting memory of him," the family said. "The phrase 'He never met a stranger' encapsulates Knapper's zest for life. He had a unique gift to make everyone feel special, and to Knapper, they all were.

"While his family, friends and players still had so much to learn from him and desperately wished they had more time with him, God called an audible and wanted to go over the game plan directly with him. It will certainly be a masterpiece, just like Greg!''

Knapp began his NFL coaching career in 1997 as a low-level offensive assistant for the San Francisco 49ers. He forged a tight bond with Young, and the two remained close. Knapp also coached for the Atlanta Falcons (two stints), Oakland Raiders (two stints), Seattle Seahawks, Houston Texans and Denver Broncos, either as the quarterbacks coach or the offensive coordinator.

"He was a tremendous football coach who achieved at the highest levels of our game, but more importantly he was a wonderful person who had the love, admiration and respect of those who were blessed to work with him," Falcons owner Arthur Blank wrote in a statement on Twitter. "Rest In Peace, Greg Knapp."

Falcons quarterback Matt Ryan also honored Knapp on social media, calling him "one of the most positive, consistent and caring coaches I have ever been around."

Jets chairman Woody Johnson also issued a statement on Knapp's death.

"In his short time with us, Greg had an immediate influence on those who had the pleasure of spending the smallest amount of time with him," the statement reads. "His legacy is not only working with some of the brightest quarterbacks the league has ever seen, but the countless others across this world he has had an indelibly positive influence on."

In addition to Manning and Young, Knapp helped tutor quarterbacks Michael Vick, Carson Palmer and Matt Ryan. His career highlight was the 2015 season, when he was a member of the Super Bowl-winning staff with the Broncos in Manning's final season.

The Jets hired Knapp to preside over their three young quarterbacks. His job, he explained last month at minicamp, was to be "the voice in the quarterback room," which includes highly touted rookie Zach Wilson.

Knapp called it an exciting challenge to coach three inexperienced quarterbacks, noting his passion for teaching. He said he got that from his parents, both of whom are teachers.

"It's invigorating for me," Knapp said.

Knapp was well-respected across the league. Young, an unofficial adviser to Wilson and his family during the pre-draft process, told ESPN in a recent interview that Knapp's presence on the Jets' staff was a "huge plus" for Wilson.

"I told his dad, Mike Wilson: If I had a son and I needed him to be coached and taken care of in a way that helps him play better football, I'd want Greg to be part of it," Young said.

Knapp, born in Long Beach, California, played college ball at Sacramento State. He never appeared in an NFL game, but he spent time on the Raiders, 49ers and Kansas City Chiefs' rosters.

The Associated Press contributed to this report.