ALLEN PARK, Mich. — Considering how the defense reacted late last season when he was injured, one of the players the Detroit Lions seemingly can least afford to lose is safety Louis Delmas.
Less than two weeks into training camp, they're now facing the same potential problem.
The Lions announced Wednesday that Delmas underwent surgery on his left knee and is out indefinitely.
Coach Jim Schwartz wouldn't speculate on whether Delmas could be back for the regular-season opener, which is 4 ½ weeks away.
"We really don't have any timetable," Schwartz said. "We'll start to make that decision as that comes closer. He's not day-to-day. He's a little more week-to-week."
Schwartz refused to release any details on the severity of the surgery, which was performed by highly respected orthopedic surgeon Dr. James Andrews Tuesday in Birmingham, Ala.
Delmas, coming off surgery last year on his right knee, had been experiencing soreness in the left knee and sitting out practices since early in camp.
"We just weren't getting anywhere with it," Schwartz said. "It doesn't do any good to have him back if he's not the same kind of player.
"That's the whole idea why we did what we did … to get him back practicing, feeling good and being healthy on the field because he does mean a lot to us. Not just from his play, but his personality, his leadership, all those things."
Delmas has started 41 games the last three years since being a second-round pick by the Lions in 2009.
The Lions went from a decent, if not good, secondary a year ago to an awful unit that ended up getting severely exposed when Delmas missed the final five games of the regular season.
Delmas returned for the playoff loss to New Orleans, but he wasn't anywhere near full strength.
"He has a big impact on our defense," said Amari Spievey, the other starting safety. "It was kind of difficult to get used to him not being out there. His passion for the game is unmatchable."
This time, Delmas' replacement is expected to be Erik Coleman, who has made 82 starts and played in 111 games during his eight-year NFL career that includes stints with the New York Jets and Atlanta.
Coleman, 30, wasn't available last year when Delmas went down because he had been put on the injured-reserve list after suffering a broken ankle in the fourth game.
"Delmas is such a great leader," Coleman said. "His presence around the football team is always felt. He plays with a lot of energy, a lot of enthusiasm. That's just contagious. That's something we're all going to have to pick up on."
Coleman is expected to start Friday's preseason opener against Cleveland.
Coleman was drafted by the Jets in the fifth round in 2004 coming out of Washington State. He was signed by the Lions in February 2011 after being released by Atlanta.
"I've tried to prepare myself to play," Coleman said. "I want to be a starter on this team. I want to help this team. I want to be a great player on this defense."
One of the ways he tried to prepare himself during the offseason for this type of opportunity was to drop about eight pounds, down to 202, to try to improve his speed and quickness.
"I tend to get too bulky," Coleman said. "I watched my diet, worked hard on the running, the explosive part of the game. I want to be more of a safety who can cover. I wanted to get back to the weight I was my first, second year in the league. There's no need for me to be a heavy safety.
"You need to run in this league and on this defense. This is a fast defense. You have to be able to get to the ball. That's what I'm going to try to do."
The Lions' other options at safety include Sean Jones (free agent from Tampa Bay), John Wendling (solid special-teams performer), Don Carey (currently out with hamstring injury) and Ricardo Silva (played four games last season).
"We've got a lot of guys who've played a lot of football," Schwartz said. "We've got some quality guys back there.
"It really doesn't matter what they look like in practice. It's how they play in games. These next four preseason games will go a long way to determine how we feel about those guys, not what they've done in the past."
