Camp Countdown presented by M&T Bank will examine some of the more pressing issues facing the team on the field as they make their final preparations for the regular season. We also focus on a few different areas that impact the team off the field. We'll address these subjects one at a time until training camp begins. Here now is the latest daily installment as we carefully probe for some of the answers the Buffalo Bills have to come up with between July 30 and the Sept. 13 opener at Ralph Wilson Stadium against Indianapolis.

Last year the Bills posted their best run defense ranking since the 2004 season. Though it slipped down the stretch Buffalo still finished 11th in the league in run defense, their best ranking since their last 9-7 season when they finished seventh overall. The 10 seasons in between the Bills ranked no better than 22nd against the run and allowed no fewer than 121 rushing yards per game in any of those years.

Last year's success was encouraging, but Buffalo is undergoing another defensive scheme change, their fifth in five seasons. The good news is Rex Ryan has a proven track record against the run and the depth and caliber of talent is virtually unchanged on the defensive side of the ball.

So can the Bills' run defense move into the upper tier of the league this fall?

Concerns and confidence

Ryan completely believes the talent he has on the defensive side of the ball is capable of being the league's top ranked defense come the end of the 2015 regular season. When it comes to Buffalo's run defense the head coach harbors one concern, the team's performance against the run on the back half of the schedule last year.

"I think the last 10 games were a little bit alarming to me because it was over five yards a carry," Ryan told Buffalobills.com.

Over their last 10 games in 2014, Buffalo gave up 4.83 yards per carry and almost 130 yards per game on the ground (129.8). Ryan knows that won't be good enough if the Bills want to end their playoff drought. In the next breath however, Buffalo's sideline boss points to his success as a defensive play caller when it comes to stopping the run and all seems right.

"I think when you look at it I've been a part of 50 games straight without giving up a 100-yard rusher when I was in Baltimore," Ryan said. "Left at 37 straight. My dad has the all-time record for games in a row without giving up a 100-yard rusher. So I feel pretty confident that we're going to be able to stop the run."

Since becoming a defensive coordinator in Baltimore, Ryan has only one season in which his run defense did not finish in the top half of the league (2012), and just two seasons when it didn't finish in the league's top 10. In six of his 10 seasons calling defensive plays for Baltimore and New York, Ryan's run defense ranked in the top five including a pair of top two finishes and three top three finishes.

So it stands to reason that Ryan and defensive coordinator Dennis Thurman will be able to take an 11th-ranked unit and raise the performance level of the run defense to a top tier ranking.

"I think that what we saw last year is if we can eliminate mental errors, we can stop the run," said Kyle Williams. "We can do just about anything that we want to. Two years ago our big problem was the big play. Somebody is in the wrong position or doesn't know what they're doing and we gave up the big play on the ground. Hopefully we eliminate those and everybody knows where they're going."

Coaching expertise

Taking that consistency further will be on Ryan and Thurman, who have shown an ability to produce steady play, not just by their choices with 'X's and 'O's, but with the kind of teaching that is more necessary than ever in the NFL.

"We have good enough players where we can line up and stop people, but really they're all about technique," said Kyle Williams of Buffalo's defensive staff. "Hands and feet for us up front, communicating so we know where we're lining up and where we're going down in and down out. Working on hands and feet then when we progress to training camp we'll get into the grinder a little bit and get into the physicality in practice."

Thurman knows the unit that has the most ground to cover is his linebacking corps with the defensive line and secondary having largely played together for three to four seasons.

"We have a young group of linebackers we're excited about," said Thurman. "Coming through OTAs and minicamp they've done well. We expect them to continue to improve. If they do, we have a chance to be a pretty special defense."

Scheme familiarity

Working in favor of Buffalo's defensive players is the new defensive scheme is largely similar to the system they played in under former coordinator Mike Pettine in 2013.

"Two years ago we basically played in this defense," said Williams. "There are going to be some changes, some guys are going to do some different things. I think we'll be able to have a good mix where we say here are our talented guys and put them out there and let them know what to do and say, 'You've got to block our talented guys.' We're also going to have defenses and looks where we're going to disguise and confuse. It's a good combination with the players we have."

One of the key players with the move to more of a hybrid scheme with some 3-4 principles is the re-assignment of Manny Lawson back to the strong side linebacker role. The veteran knows how to make pre-snap reads and adjustments and that will benefit both defensive quarterback Preston Brown and the defensive unit.

"He's talking a lot more because he's stacked so he can see the whole formation," said Brown. "So it's good to have an older guy to give his impressions of what he's seeing out there and we spread it around the field."

Though Brown played some 3-4 looks in college at Louisville, the defense will be in stark contrast to the system he played in under Jim Schwartz last year. A player wise beyond his years, Brown took the change well.

"The biggest difference is you're two gapping," Brown said of the linebacker responsibilities. "You can't just hit the gap because you'll be out of position and they'll hit the gap you're not in. So you've got to wait on the back and read off of him. You've got to go and face the guard every play. It's fun for me going against guards, but it's just a different mentality."

Poised to succeed

Knowing only two players that played roles in the starting 11 on defense last season are not back the odds are good that Buffalo can push their run defense rank into the top 10 in 2015. Even more encouraging is the fact that in Ryan's first season as coordinator in Baltimore, the Ravens ranked ninth against the run. In his first season as head coach of the Jets, his run defense finished eighth against the run.

"We have the chance to move from a very good defense to an elite defense," said Thurman.