SANTA CLARA, Calif. - Thomas Herrion often sought Jeremy Newberry's help. The 23-year-old offensive lineman and his veteran teammate worked on their technique together before practice, with Herrion seeking any edge that might help him make it in the NFL.

The San Francisco 49ers went back to work Monday without Herrion, who collapsed and died Saturday night after a preseason game in Denver.

But Newberry imagines the Niners will remember their fallen teammate - his work ethic, his humor and his spirit - for the rest of their lives.

"He was kind of dear to me," said Newberry, a two-time Pro Bowl player. "The guy was a hard worker. I never heard him complain about anything, man. He always wanted to do better. We lost a special person. It's a sad day for everybody around here."

After several hours of meetings and mourning, the team held a light afternoon practice. In the subdued atmosphere at their training complex, Herrion still was central in the 49ers' minds four days before their next preseason game.

"It was a waste for me," left tackle Jonas Jennings said of the hour-long workout. "Mentally, I wasn't there. But you've got to be a professional. You've got to do what's expected of you."

Authorities might not know the cause of Herrion's death for weeks, but no answer will seem logical to his teammates. His fellow offensive linemen got another sobering reminder of their profession's risks and the physical extremes required to play it well, though no link has been established between Herrion's weight - well over 300 pounds - and his death.

"It's something you don't like to think about every day," Newberry said. "I think the life expectancy for an offensive linemen isn't real great. Me having young children, that's a somber point, but it's part of your job. ... (A player could) try to play at 200 pounds, but that isn't going to happen."

There were flower arrangements in the complex's lobby, and grief counselors were available. The 49ers, who had a regular day off Sunday, canceled their Monday morning practice and closed their locker room to reporters.

A rap track, recorded by rookie Fred Amey and dedicated to Herrion, was played for the team during the morning meeting. Team physician Barry Bryant briefed the players on what they saw in the locker room in Denver, where Herrion collapsed shortly after the team recited the Lord's Prayer. Later, the team chaplain and a crisis expert also addressed the players, who still were clearly shaken by Herrion's death.

"I knew it wasn't good when it happened," said guard Justin Smiley, who was kneeling next to Herrion. "It's definitely scary. Every now and then, something brings you back to reality."

Herrion played only in the final minutes of the 26-21 loss to Denver. He was on the field for San Francisco's 14-play, 91-yard drive shortly before the final whistle.

"He reminded me of myself in college - just a raw talent, eager to learn," Jennings said. "He was really coming into his own. He just had one of the best drives of his life, right before his life was taken."

Quarterback Alex Smith, the No. 1 draft pick who played with Herrion at Utah in 2003, wasn't ready to speak to reporters.

"I think he's taking it pretty well, but I know it's tough," Smiley said of Smith.

Everyone in the organization is expected to attend a private memorial service Tuesday night in nearby Mountain View - but the team also must move forward in the relentless NFL preseason.

The 49ers host the Tennessee Titans on Friday night in their third exhibition game. Herrion's funeral will be held Saturday in his native Fort Worth, Texas, with NFL commissioner Paul Tagliabue, coach Mike Nolan and team owners John York and Denise DeBartolo York expected to attend.

The 49ers will wear a black decal with Herrion's No. 72 on the back of their helmets this season, and Herrion's locker near the door to the practice fields will remain unchanged.

The Denver coroner's office performed an autopsy Sunday, but a spokesman said no cause of death could be determined until coroners receive the results of toxicology and tissue tests, which usually take about three to six weeks.

Many possible factors in Herrion's death will be discussed before then, including Denver's high altitude, proper hydration and excessive weight. Herrion's weight was average for an NFL lineman, but obese by many conventional standards.

Some physicians cite a high body-mass index (BMI) - a height-to-weight ratio that doesn't consider body muscle versus fat - as an indicator of many potential health problems.

Others believe BMI is "not a proper indicator of health status," as Dr. William Kraemer of the National Strength and Conditioning Association determined with detailed research for a soon-to-be-published study on the 2003 Indianapolis Colts.

Four years ago, Minnesota Vikings offensive lineman Korey Stringer died of heatstroke following a practice in steamy weather. In 2002, retired Saints defensive lineman Frank Warren died of a heart attack at 43. Reggie White's death last December might have been caused by sleep apnea - a condition commonly afflicting obese people, including Newberry.

The San Francisco Giants held a moment of silence for Herrion before their game Monday night against Philadelphia. Tributes to Herrion also poured in from his native Texas and Utah, where Herrion played his final two college seasons.

The Utes will hold a moment of silence before the season opener against Arizona on Sept. 2, and they'll add a black No. 76 to their helmets. Coach Kyle Whittingham will attend Tuesday's memorial service, and the school will fly several former Utah teammates - including Brandon Warfield, a running back who was Herrion's best friend throughout college - to the funeral.

"It hurts every time you walk in the locker room and his locker is still up," said Arnold Parker, a 49ers defensive back who played with Herrion at Utah. "Every time somebody from Utah calls me, it makes you think of Big T. ... He dreamed of being in the NFL, and his dream came true. It's sad that it's over for him, but it's a testimony that dreams come true."