ALLEN PARK, Mich. -- Terrell Owens wouldn't recognize the Michigan coming out in his former boss, Steve Mariucci. Michigan Mooch is one tough hombre.

Tywan Mitchell, a tight end signed for depth over the weekend, failed to hustle downfield on a possession pass play. Mariucci got in his face and sternly said, "You got to get up and go." Within minutes, he prodded running backs to finish carries in team drills that start at the opponents 30-yard line and always end up in the end zone. Any lack of attention to detail brings out the fire in Mariucci.

	Steve Mariucci was 60-43 in six seasons as the 49ers head coach.

Could this be the same former 49ers coach whom Owens complained didn't generate the killer instinct among his players, subsequently resulting in a win for his buddy, Dick Jauron, during a game against the Bears two years ago? Same guy, different environment. Mariucci, who was a San Francisco treat as a successful 49ers coach, is letting his labor intensive Michigan roots come out as the Lions new coach.

"I did that sometimes in practice with the 49ers," Mariucci said of his "in-your-face" style. "Maybe not every practice but when need be. We have to establish how we are going to do things here. To me, that's going to be as important as winning football games. We have to set a standard, a way of life."

The 49ers weren't conducive to this type of coaching. Since the 1980s under Bill Walsh, the 49ers were a veteran team. Walsh kicked butt early. He established the work ethic required to be a championship contender year in and year out. Mariucci came in as a little bit of an outsider even though he was popular as the head coach at California.

Why scream when not needed? Mariucci coached maturely yet passionately until politics did him in after the 2002 season and the franchise let him out of his contract. Mariucci bounced back with a $5 million a year contract from Detroit and a fresh start.

Unfortunately, he takes over a bad team, a team that started last season as the second oldest in football and went 3-13. Unlike the past two years, Mariucci knows he must go young. Quarterback Joey Harrington is in his second season. Featured receiver Charles Rogers is a rookie. His second and third cornerbacks -- Chris Cash and André Goodman -- are in their second seasons.

"We've got a group of veterans, but not many," Mariucci said. "We have to develop some leaders here. We've got 32 rookies and a lot are going to make the team. On the field, in the meeting rooms, off the field, we are trying to establish how we are going to be Detroit Lions and professionals."

Bill Parcells is doing the same thing in San Antonio -- trying to change years of underachieving with the Cowboys. Little things. Too bad team president Matt Millen couldn't have pulled Mariucci out of his fatalistic situation in San Francisco two years ago. Ford Field opened last year with an Edsel, a horrible team that played hard but played bad. Millen wanted Mariucci but settled for his offensive coordinator, Marty Mornhinweg, who couldn't win with a patched up roster.

"I was looking on the football side," Millen said about his hiring of Mornhinweg. "I paid attention to the X's and O's and that's wrong. (Vince) Lombardi was an excellent X's and O's coach but when it comes to football, it's a people's business. You try to read into things like what makes Lombardi Lombardi, what makes (Don) Shula Shula. It's people skills. Steve has them."

Winning in the NFL requires more than just people skills. It requires skilled people. The Lions are assembling that crew, but it's going to take a couple years. The Lions are way too young at the key positions -- quarterback, flanker, cornerback, and defensive end. One problem that sacked Mornhinweg last year was injuries, and that curse hasn't gone away.

Mariucci opened camp with nine players on some form of a physically unable to perform list. Some of those players are vital to the development of the franchise -- defensive end Kalimba Edwards, halfbacks Shawn Bryson and Artose Pinner, tight end Mikhael Ricks, defensive tackle Luther Elliss and on and on. If that wasn't bad enough, first-round pick Rogers suffered an open dislocation of the left ring finger and backup tight end John Owens broke a bone in his hand.

But at least the Lions spirit hasn't been broken.

"Coach Mariucci is a very, very precise, very detail-oriented person," Harrington said. "He speaks in a meeting and acts it on the field, and that's what people respect. That's why people here are rallying around him. He tells you exactly what he wants on the field. He hammers it home and doesn't expect anything less than perfect."

Take Harrington, for example. He's a perfectionist himself. He plays concert piano in his spare time, but dwells on the fundamentals of his craft. Harrington, with the help of Mariucci and assistants, worked on his throwing mechanics, cadence, huddle management and reading progressions while making throws.

His goal is to be a 70-percent thrower, hoping to achieve the success of Chad Pennington of the Jets or of former 49ers quarterback Steve Young. For that to happen, though, Rogers must be an 80-catch plus receiver and the rest of his receiving corps must get in sync with him.

	"	Coach Mariucci is a very, very precise, very detail-oriented person. He speaks in a meeting and acts it on the field, and that's what people respect. That's why people here are rallying around him. He tells you exactly what he wants on the field. He hammers it home and doesn't expect anything less than perfect. "
		— Joey Harrington, Lions quarterback

Lions receiver Shawn Jefferson, who watched Falcons quarterback Michael Vick emerge as a force last season, doesn't doubt that Harrington can accomplish similar success this year.

"Vick can take a ball and run it 80 or 90 yards whereas Joey is probably not likely to run away from anybody but he's going to beat you upstairs and with his arm," Jefferson said. "Don't get me wrong. To compare them, the thing that sticks out the most about both of thee guys is that they want to win. I like the way he takes control of the team.

Joey commands respect in the huddle. Everybody shuts up and listens to him. Both are intense players, but I think Joey is ahead of Vick for a quarterback going into his second year. Joey seems to understand this whole system better."

The downfall of the offense, though, could be the injuries. A year ago, Millen brought in Bill Schroeder and Az-Zahir Hakim, but that wasn't enough. Hakim started at flanker, but his body couldn't hold up. He caught only 37 passes in 10 starts. With Rogers taking over at flanker, Hakim fits into his more natural role as the slot receiver. Schroeder's more of a natural split end, but the injuries around him forced Schroeder into more routes across the middle. He caught only 36 balls.

"Last year, Bill was our threat because he can run," Harrington said. "He was doing everything last year. Az was injured, so Bill was getting all the coverage. With Rogers there, we can take some coverage off Bill. Not having defenses focus on him is going to allow him to do a lot of things."

But this is the Lions and their luck hasn't been good when it comes to injuries. Mariucci arrived and came to an important conclusion after their first minicamp: They were dangerously thin at receiver and linebacker. So, the Lions drafted three receivers and signed Jefferson. At linebacker, the Lions signed veterans Earl Holmes and Wali Rainer.

Owens may have been too openly critical of Mariucci and forgot how well Mooch works with young players. Go back to 2000 when the 49ers were coming out of salary cap hell and couldn't add players until the draft.

From May until September, Mariucci coached up a bunch of draft choices and undrafted minimum salary players to a 6-10 season that started to come together in the second half of the season. Seven rookies started that year on defense. That group, which included Julian Peterson, Ahmed Plummer, John Engelberger and Jason Webster, became the core group that went back to back in the playoffs for Mariucci.

That's the Lions on offense. They will hit their stride when Rogers and the other young players develop on offense. Rogers is much more coachable than anyone imagined. He's professional in his approach and hard-working. Harrington loves his speed. Rogers once ran 10.26 in the 100-yard dash and 47 seconds in the 400. Over the next two years, he'll need to add upper body strength to get off press coverage.

"We have a lot of key people who are really young," Millen said. "It depends on how fast they mature. If they mature fast, we'll make a little bit of noise. If they don't, we'll struggle."

And if they don't, Mariucci will be in their young faces trying to get them to perform better. He's having fun doing that.

John Clayton is a senior writer for ESPN.com.