Mike Singletary made up his mind, and nothing was going to change it.

He decided, at age 12, to run away from home because his parents had forbidden him from playing football. He told his mother his plans, and to this day insists he was serious.

His father was a Pentecostal minister who refused to let Mike and his brothers play football. He viewed it as the "devil's workplace" because of its violence.

But the pull was too strong for the youngest of the Singletarys' 10 children. Even at an early age, the desire burned deep inside him. Singletary couldn't resist the temptation, knowing full well the consequences.

He passed by daily sandlot games at the park between school and his home in Houston. Without fail, he jumped in and played ... then endured a spanking when he got home. He hated his dad's spankings, but the pain was worth the chance to play football.

Finally, he saw an opening when his parents divorced.

"I begged my mom and I begged my dad into letting me play," he said. "I think they saw the desire and they let me play."

From that humble beginning sprouted a Hall of Fame career and indelible image of a wide-eyed middle linebacker screaming, "I like this kind of party" as the heart and soul of the famed Chicago Bears defense of the 1980s.

That was Samurai Mike, the two-time NFL Defensive Player of the Year and 10-time Pro Bowl linebacker. Today, he is Vikings linebackers coach and head coach Leslie Frazier's close friend and confidant.

Singletary, 52, is more laid-back than he was during his playing days. But his desire and love of football remain as strong as ever. He joined Frazier's staff after a turbulent stint as the San Francisco 49ers head coach but if his focus is more micro as a position coach, his vision remains intact.

"We may not be the best team on the field talent-wise, but my team, the one thing they're going to be is physical," he said. "They will fight you every down."

Every so often, Singletary and his wife, Kim, will see an old clip of his playing days and laugh when his eyes become the focus.

"He's like, 'Why are they always showing me looking crazy?' " Kim said. "I'm like, 'Because you always look crazy.' "

Those eyes became his trademark as a player, opened with an intensity that could hush a room in an instant. If a person's eyes are the window to the soul, Singletary's leave little doubt about his conviction.

"Sometimes he'll say something and I'm like, 'Why are you looking at me like that?' " Kim said. "He's crazy-looking, but he doesn't realize it. Every one of the kids knows [that look]."

Music man

Kim and their seven kids (ranging in age from 25 to 13) also see the different side, the anti-Samurai Mike. They know the guy who loves to dance, cries during movies, and sings Frank Sinatra and Barbra Streisand songs. His musical tastes range from Motown to Lady Gaga.

Samurai Mike? Lady Gaga?

"And Cee Lo Green," said son-in-law O.J. Atogwe, a safety for the Washington Redskins. "You know that song, 'I see you driving 'round town with the girl I love?' He's always singing that song."

Atogwe married Singletary's daughter Jill in May. He met his future father-in-law several years ago and understandably felt nervous.

"He was [intimidating] for the first 10 seconds, but after that he's such a calm and mild-mannered man that the tension went away immediately," Atogwe said. "There's another side to him."

Kim Singletary describes her husband's public vs. private persona as "Jekyll and Hyde." He becomes Mushy Mike around their first grandchild, a girl born in July. Sometimes Kim comes home to find music blasting through the house as her husband of 27 years dances. "He's a very good dancer," she said.

This is not to suggest he's a pushover around the house. Singletary's retirement in 1992 meant he had more time to spend with his family, which made Kim wonder how he would channel his intensity. She wasn't surprised when she walked into the kitchen and found him teaching the kids the proper way to load and unload the dishwasher.

"He had them lined up," she said. "They were practicing. [He said], 'No, do it again. That's not right, do it again.' I was afraid that was what would happen, and it's exactly what happened."

Though he had offers to get into coaching soon after his playing days, Singletary resisted that urge because he wanted to spend time with his family. The long hours required of coaches didn't mesh with his beliefs about his parental responsibilities.

"I wanted our kids to know that I love them, and I wanted them to know me," he said. "Not just know me as Mike Singletary the football player, but know me as a man, as a father. To be able to take some of my life and invest it in them. That was very important to me."

Straight and narrow

Singletary's high school teammates always teased him because of the way he played. He gave maximum effort on every play, even in practice. They wondered what was wrong with him. A few even asked if he was on drugs, saying no one tries that hard.

For Singletary, playing football was a privilege, not a right, and should be treated as such. His first football coach pulled him aside one day and offered prophetic words.

"He said, 'Son, you may be small, but there's something in there,' " Singletary said. "There's something in you that's going to allow you to go places.' "

Former Baylor coach Grant Teaff noticed it. The coaching staff loved Singletary's intensity, but he was such a whirling dervish on the field that he didn't listen to anyone. Teaff instructed defensive coordinator Corky Nelson to ignore Singletary in practice, and didn't let any coach even say his name. On the second day, Teaff stood at the opposite end of the field when he heard Singletary let out a "blood-curdling" scream demanding for someone to say his name.

"He wanted to hear somebody yell at him," Teaff said. "Coach Nelson said, 'We'll call your name if you'll start listening.' From then on, he was the most coachable guy in America."

Singletary had Mike Ditka as his NFL coach, so getting screamed at was never a problem. But he quickly became a Ditka favorite.

"He was all business," Ditka said. "I don't think anybody prepared any better than him. He was just a hell of a football player."

Singletary finished his NFL career with 1,488 tackles, including 885 solo. But his Hall of Fame career was built more on determination and instincts than God-given talent, he said.

"I'm not a guy you look at and would pick to be on your team," he said. "I believe you can do anything if you have a little bit of talent and a lot of desire and you're really willing to put the time in."

Pants on the ground

Singletary was a coach's dream, but his dream was not to coach. He became a successful motivational speaker and hosted leadership seminars after retirement. Frazier urged Singletary to consider coaching every summer when they hosted a youth football camp together. The two had become close friends as rookie roommates with the Bears. There was just something about the way Singletary interacted with the kids at their camp that impressed Frazier.

"I would look at him and watch him and say, 'Man, he could be such a great coach,' " Frazier said. "But it wasn't the right time."

The time finally came in 2003, when Baltimore Ravens coach Brian Billick hired Singletary to coach linebackers. He took the same position with the San Francisco 49ers before being elevated to interim head coach in 2008 after Mike Nolan was fired.

In his first game as head coach, Singletary sent tight end Vernon Davis to the locker room with 10 minutes left in the fourth quarter after he received a personal foul penalty. Singletary then delivered an "I want winners!" postgame rant that became a YouTube sensation. It later was revealed that Singletary dropped his pants during his halftime speech to let his players know they were getting their rears kicked.

Ditka loved the show of emotion.

"There comes a time when you've got to call players out," he said. "That's all there is to it. It was a little easier when I was coaching than it is now because these guys all get their feelings hurt so damn easy. But what he did was right, believe me."

The 49ers appeared headed in the right direction under Singletary when they played the Vikings at the Metrodome early in the 2009 season. A 3-0 record was within their grasp until Brett Favre delivered a crushing blow with his last-second touchdown pass to Greg Lewis in the back of the end zone.

"It was one of those games where it was a measuring stick for us," Singletary said. "It would have done a tremendous amount to give us that belief that every team has to have that's a young team, new head coach, you're not quite sure is this the direction. That game probably would have taken us to another level."

Instead, the 49ers finished the season 8-8 and failed to make the playoffs, setting the stage for a disastrous 2010 season that started with five consecutive losses. Singletary oversaw a quarterback carousel with Alex Smith and Troy Smith and fired his offensive coordinator, Jimmy Raye, after the third game.

The 49ers quarterback situation was a mess, and they ultimately didn't win enough to save Singletary, who was fired last December after going 18-22 in two-plus seasons.

He joined Frazier's staff a few weeks later without requiring a formal interview. Singletary said he's comfortable in his new role and happy to be with Frazier, but he "absolutely" wants another chance to be a head coach again some day.

"However long I'm here, I want it said when I'm gone that, 'Coach Singletary gave this program everything he had and more,' because that's what I'm going to do," he said.