Raiders coach Dennis Allen was in Texas after the death of his father Grady, a former Falcons LB. (US Presswire)

The Raiders continued preparing for Thursday night's game against Denver without coach Dennis Allen, whose father, Grady, died Monday night in the Dallas area at 66 after suffering a heart attack last week.

Allen flew to Dallas after Sunday night's game against Cleveland to be with his father,  a former Atlanta Falcon linebacker. He expects to return to Oakland on Wednesday night and be on the sidelines for Thursday night's game. Offensive coordinator Greg Knapp ran practice Tuesday.

"Tough situation, obviously, for coach," QB Carson Palmer said Tuesday after practice. "Our team got together and we're going to support him and do whatever he needs us to do, and right now that's prepare for this game and get ready for the Denver Broncos. Our thoughts and prayers are with him and his family right now as they're going through this.

"Coach Knapp stepped in and filled in and did a phenomenal job and really took charge of the meetings the way that D.A. does and handled practice the same way that D.A. does. It's a challenge. We understand he just needs some time away and a chance to be with his family. What we need to do for him is prepare, get ready to play this game and focus on this game and be as prepared as we can in a short amount of time for when he returns."

The Raiders have had their share of off-field tragedies this season. Defensive line coach Terrell Williams' son, Tyson, died of an illness at the age of 4 earlier in the season. 

"It's always hard, man," Raiders linebackers coach Johnny Holland said. "It's been a tough year for our staff as far as going through adversity. And to lose your father is a tough situation. Our prayers are definitely out for Dennis and his family, and I can imagine what he's going through now.

"We just want to make sure that while he's away we know what he expects, and we know what to expect. And our guys today looked like they stepped up to the challenge and did a very good job with what we're supposed to do."

Allen spent last season with the Broncos as coach John Fox's defensive coordinator. Fox, during a conference call with Bay Area reporters, said that he and most of his assistants met Grady Allen last season when he attended practice.

Fox said he texted his condolences to Dennis Allen.

"Our thoughts and prayers are with the Allen family, and (Dennis) is where he needs to be," Fox said. Sometimes we get a little caught up in what we do for a living and those types of things, but if that was something he would have asked me, I would have said you need to be with your family."

Injury updates: Starting FS Matt Giordano and backup S Mike Mitchell passed all their concussion tests and were cleared for Thursday night's game. They practiced Tuesday but were limited. CB Phillip Adams, who also suffered a concussion against Cleveland, has not passed all of his tests and did not practice.

Starting DT Richard Seymour (hamstring/knee) missed practice again and will likely miss his fifth-straight game Thursday.

Ten players in addition to Giordano and Mitchell were limited in practice: OT Khalif Barnes (triceps), DE Jack Crawford (toe), WR Juron Criner (shoulder), RB Mike Goodson(ankle), RB Taiwan Jones (ankle), RB Darren McFadden (ankle), TE Brandon Myers (shoulder) and FB Marcel Reece (hamstring/quadriceps).

Add one: The Raiders signed RB/FB Jamize Olawale off the Dallas Cowboys' practice squad to their 53-man roster Tuesday. Olawale said the Cowboys tried to convince him to stay but didn't make him a firm offer to join the 53-man roster before he signed with Oakland.

"They were just trying to play games, I felt, so I came out here," Olawale said.

This is a homecoming of sorts for Olawale. He was born in San Francisco and spent time at St. Ignatius High School in San Francisco and De La Salle in Concord before finishing at Long Beach Poly. He attended El Camino Community College for two years then transferred to North Texas for his final two. Dallas signed him as an undrafted rookie this year.

Olawale said he spent one season at North Texas as a wide receiver but has played fullback, H-back and running back. His favorite position is running back.

"I love playing running back," Olawale said. "I feel like I can do a lot of damage at running back. But I'm whatever they need me to play."

"Big back," running backs coach Kelly Skipper said of the 6-foot-1, 240-pound Olawale. "We watched him a little today. He can move around. He's got good hands. Looked like a pretty good athlete. We'll see more about him as we go."

Follow Raiders reporter Eric Gilmore on Twitter @CBSRaiders.