The Kansas City Chiefs' defense is in serious need of a boost.

It will get one in a big way when star pass-rusher Tamba Hali makes his 2012 debut Sunday at Buffalo. Hali served a one-game NFL suspension in Week 1 for violating the league’s substance abuse policy. The Chiefs were run over, 40-24, by the visiting Falcons.

Hali -- who told reporters “it wasn’t fun screaming at the TV” while he watched the Falcons dismantle the Chiefs -- was one of four Kansas City defensive starters who missed the game. However, the Chiefs did not miss any of the players more than Hali. Hali simply makes the Chiefs a different defense, and the Chiefs know it. That’s why it is a relief that he will flying to Buffalo, where the Chiefs will try to even their record at 1-1 and bring life to what is a promising season. Hali is one of the best pass-rushers in the NFL.

Without Hali to create a consistent pass rush, Atlanta quarterback Matt Ryan was able to relax and pick apart the Chiefs. The Chiefs sacked Ryan once and barely created much of a pass-rush burst. That’s not a surprise. When Hali -- who has 53.5 sacks in six NFL seasons and 26.5 sacks in the past two seasons -- was not on the field last season, the Chiefs registered a grand total of zero sacks, according to ESPN Stats & Information.

“We all know that Tamba brings a lot to the table as far as his ability to rush the passer,” Kansas City coach Romeo Crennel told reporters this week. “When you have that kind of pressure that you can apply to an opposing offense, that’s good for us and bad for them. They have to be concerned about it. We’ll get him back and hopefully he’ll be at a level that he can impact the opponent and then be able to help us win some games.”

Can one player make that much of a difference?

A player of Hali’s caliber can. Pass-rushers are at a premium. Hali, a first-round draft pick from Penn State in 2006, is the best defensive player in the AFC West in my opinion, although Denver pass-rusher Von Miller is making a serious push. I’m not alone in my high praise.

Last year, when he was still the defensive coordinator in Kansas City, Crennel said Hali was the best edge rusher he’d ever coached. Scouts rave about his relentless motor and marvel at how he never gives up on plays. Hali is that he is a complete player. He is more than simply a pass-rusher. He is unwavering against the run, too.

“You see him play; you see the energy he displays in the game,” Crennel said. “And that’s what he is; he is a high-energy guy. He’s always working at his craft, trying to get better all the time. That’s what he brings to the table. The guys in the locker room appreciate the energy that he brings.”

Matt Williamson of Scouts Inc. says Hali is an elite player but is often overlooked, perhaps because he plays in the middle of the country and is not a flashy player at a position where there is a high-flash factor. Hali has a reputation for being quiet and humble. He doesn’t talk to the media much and he never boasts. So, he may get lost in the hoopla when it comes to the game’s best sack artists.

He has been voted to the last two Pro Bowls, and he played in the game last year. Earlier this summer, Hali addressed the fact that he may be a little off the radar.

“I think guys see that I play the game and I have a passion for it,” Hali said. “I hope that [the media] respect my craft, but I don’t really pay attention to it much.”

There is no doubt Hali has earned the respect of his peers. Tight end Kevin Boss considered being on Hali’s side a bonus for signing with the Chiefs. Boss had to tangle against Hali last year while with the Raiders.

You know a defensive player is special when opposing offensive coordinators game-plan specifically to neutralize that player. Boss said that was the case in Oakland last year. Stopping Hali was the top priority.

“You knew guys like Tamba Hali,” Boss said in training camp. "We had to draw a big red circle to make sure we knew where he was at all times when we were playing against him.”

Be certain that somewhere deep within the halls of the Bills’ facility this week they are circling No. 91 in Chiefs red. The Falcons didn’t have to do that in Week 1, and the Chiefs paid for it.