Months after revamping their defensive end position, the Bears will finally get a chance to unveil their prized free agent acquisitions in a game that counts Sunday at Soldier Field.

Veterans Jared Allen, Lamarr Houston and Willie Young all are expected to help a once-proud defense rebound from a disastrous 2013 season beginning this weekend against the Buffalo Bills.

Allen played in only one preseason game this summer, missing time with a sore shoulder and to be with his wife when she gave birth to their second child. But the five-time Pro Bowler has no doubt that he's prepared to start his 11th NFL season.

"Coach took good care of me," Allen said. "I'm ready to go. I think for me at this point in my career, I know the process my body has to go through and what my mind has to go through to get ready for Week 1. I'm ready to go."

Houston appeared in all 64 games with 60 starts over the last four seasons with the Raiders, recording 226 tackles, 16 sacks, one interception, five passes defensed, 37 tackles-for-loss, four forced fumbles and six fumble recoveries.

The 6-3, 300-pounder appealed to the Bears in part because his 136 tackles over the past two seasons were the most in the NFL by a defensive end in a 4-3 system. Plus he compiled those stats while playing all four defensive line positions and lining up in two-point and three-point stances.

Since joining the Bears, Houston has been everything they expected and more.

"It really starts in the locker room," said coach Marc Trestman. "He comes in every day consistently with a smile on his face. He has fun. He works really hard. He's a finisher in practice. He runs to the ball. You notice him out there. His strength, you notice that in training camp. He's playing against taller, longer players all the time and he's able to control them.

"Just the overall personality is good for our locker room in terms of just how he acts every day in terms of just getting along with everybody and having fun. But when he's out here and the ball is snapped, he's working. He's on top of things. He's a pleasure to have around."

Houston possesses tremendous versatility, which gives the Bears flexibility up front. In passing situations, he can move inside to tackle, enabling Young to enter the game at end.

"The beauty is because we have Willie in the picture, too, we can get them all on the field at the same time and they can be comfortable in those positions," Trestman said. "When Lamarr goes inside he likes it. He likes having opportunities to attack a different offensive player along the way.

"That just adds tremendous value for a guy who can be a pass-rushing, run-stopping defensive end and a pass-rushing three-technique or defensive lineman depending on how we play him."

Young spent the past four seasons with the Lions, recording 72 tackles, six sacks, 11 tackles-for-loss, seven pass breakups and two fumble recoveries. The 6-4, 251-pounder started for the first time last season, opening 15 of 16 games and establishing career highs with 47 tackles, three sacks, seven tackles-for-loss, five pass breakups and two fumble recoveries.

Trestman first met Young in 2005 when the two were at North Carolina State.

"I've always liked Willie," Trestman said. "I watched him as a puppy when he came into N.C. State and watched him grow up. I've always followed his career. I just love the way he works and plays.

"He came in and worked his tail off. He's another guy with a smile on his face always. He created havoc for us last year in the two games we played [against the Lions]. I'm really excited to have him. To have three ends like that and one flexible enough to go inside adds a lot of value to our football team."

Months after revamping their defensive end position, the Bears will finally get a chance to unveil their prized free agent acquisitions in a game that counts Sunday at Soldier Field.

Veterans Jared Allen, Lamarr Houston and Willie Young all are expected to help a once-proud defense rebound from a disastrous 2013 season beginning this weekend against the Bills.

One of the NFL's most prolific pass rushers, Allen has recorded 128.5 sacks in 10 seasons with the Chiefs and Vikings. He led the league in sacks in 2007 and 2011 and has averaged 14.5 sacks over the past seven seasons, never registering fewer than 11 during that span.

Allen played in only one preseason game, missing time with a sore shoulder and to be with his wife when she gave birth to their second child. But the five-time Pro Bowler has no doubt that he's prepared to start his 11th NFL season.

"Coach took good care of me," Allen said. "I'm ready to go. I think for me at this point in my career, I know the process my body has to go through and what my mind has to go through to get ready for Week 1. I'm ready to go."

Houston appeared in all 64 games with 60 starts over the last four seasons with the Raiders, recording 226 tackles, 16 sacks, one interception, five passes defensed, 37 tackles-for-loss, four forced fumbles and six fumble recoveries.

The 6-3, 302-pounder appealed to the Bears in part because his 136 tackles over the past two seasons are the most in the NFL by a defensive end in a 4-3 system. Plus he compiled those stats while playing all four defensive line positions and lining up in a two-point and three-point stance.

Since joining the Bears, Houston has been everything and more than they expected.

"It really starts in the locker room," said coach Marc Trestman. "He comes in every day consistently with a smile on his face. He has fun. He works really hard. He's a finisher in practice. He runs to the ball. You notice him out there. His strength, you notice that in training camp. He's playing against taller, longer players all the time and he's able to control them.

"Just the overall personality is good for our locker room in terms of just how he acts every day in terms of just getting along with everybody and having fun. But when he's out here and the ball is snapped, he's working. He's on top of things. He's a pleasure to have around."

Houston possesses tremendous versatility, which gives the Bears flexibility up front. In passing situations, he often moves inside to tackle, enabling Young to enter the game at end.

"The beauty is because we have Willie in the picture, too, we can get them all on the field at the same time and they can be comfortable in those positions," Trestman said. "When Lamarr goes inside he likes it. He likes having opportunities to attack a different offensive player along the way.

"That just adds tremendous value for a guy who can be a pass-rushing, run-stopping defensive end and a pass-rushing three-technique or defensive lineman depending on how we play him."

Young spent the past four seasons with the Lions, recording 72 tackles, six sacks, 11 tackles-for-loss, seven pass breakups and two fumble recoveries. The 6-4, 251-pounder started for the first time last season, opening 15 of 16 games and establishing career highs with 47 tackles, three sacks, seven tackles-for-loss, five pass breakups and two fumble recoveries.

Trestman first met Young in 2005 when the two were at North Carolina State.

"I've always liked Willie," Trestman said. "I watched him as a puppy when he came into N.C. State and watched him grow up. I've always followed his career. I just love the way he works and plays.

"He came in and worked his tail off. He's another guy with a smile on his face always. He created havoc for us last year in the two games we played [against the Lions]. I'm really excited to have him. To have three ends like that and one flexible enough to go inside adds a lot of value to our football team."