KANSAS CITY, Mo. (AP) _ To learn the effect of Derrick Thomas' death, Christian Okoye had only to get in the car with his daughter.

``Daddy, wear your seat belt,'' 8-year-old Tiana said.

And Okoye, a Kansas City running back when Thomas broke into the league in 1989, reached down and buckled up.

``I thought, `Wow, this is a big lesson,''' he said. ``Sometimes I forget to do that.''

Okoye joined 22,750 fans at Arrowhead Stadium on Monday who filed past the open casket of the nine-time All-Pro linebacker who died Feb. 8 of complications from a traffic accident.

Today, in a service at Kemper Arena, Kansas City planned a final farewell. In a two-hour service, scheduled speakers included NFL commissioner Paul Tagliabue and Hall of Fame quarterback Joe Montana.

On Monday, Thomas' open casket sat in Arrowhead Stadium's east end zone, near the spot where he once sacked John Elway and recovered a fumble for a touchdown that clinched a playoff berth.

Bundled against a cold February wind, fans walked single file and two-by-two down the stadium steps and into a white tent where a spray of roses sat next to the casket. Thomas' body was dressed in a light gray business suit.

In honor of this son of an Air Force pilot who never returned from Vietnam, a B-2 Stealth bomber came in so low its belly seemed to scrape the scoreboard.

For the flyover, almost everyone who works for the Chiefs _ owner Lamar Hunt, general manager Carl Peterson, coaches, secretaries and maintenance men _ stood silently on the field facing the tent.

``This is the saddest day in Kansas City sports history,'' said Steve Warczakoski of Kansas City, Kan. ``My favorite football player of all time.''

One woman carried her 9-month-old daughter down the steps.

``Someday she'll be able to say she was here,'' the woman said.

Thomas was just a few weeks past his 33rd birthday when his Chevrolet Suburban skidded on an icy highway Jan. 23 and flipped several times. The crash killed his best friend and left one of the NFL's most feared pass rushers paralyzed from the chest down.

Thomas and his friend were both thrown from the car. A third passenger, the only one in the car wearing his seat belt, walked away with minor injuries.

``I've got Derrick's No. 58 taped to my steering wheel,'' said Darren Bradley of Raymore, Mo., who took a day off work to pay his respects. ``Every time I turn the ignition key I'll think of Derrick and I'll buckle up.''

The nine-time All-Pro was transferred to a hospital in his hometown of Miami and was said to be improving. But on Feb. 8 a blood clot in his legs created a pulmonary embolism that killed him almost instantly.

Since that day, fans have gathered at a candlelight vigil, created a memorial of poems and flowers at Arrowhead's wrought iron gates and donated more than $25,000 to his Third and Long Foundation, which encourages youngsters to read.

Among the mourners Monday was Fred Patek, a star shortstop for the Kansas City Royals during many of their glory years in the 1970s.

His daughter Kim was paralyzed in an accident in 1992 not far from Thomas' crash. Kim Patek had no insurance, and a big part of the expenses until she died three years later was paid for by fans' donations and events like charity basketball games between Chiefs and Royals players.

``What I think back to most of all is how this community comes together and all the beautiful people there are in this town,'' Patek said. ``All the things they did for me and all the things you see now, what's happening.''

He stopped to wipe a tear.

``It kind of stirs up a lot of things in my past. But I guess the thing most of all _ it really hit me _ you can't believe.''

He could say no more. He apologized and vanished into the crowd.