Buffalo Bills' 2018 free agency: AJ McCarron likely a QB bridge to draft pick

Bills to lock in Lotulelei with 5-year deal (0:43)

Adam Schefter and Louis Riddick weigh in on the Bills picking up former Panthers DT Star Lotulelei when free agency opens. (0:43)

A breakdown of the Buffalo Bills' 2018 free-agent signings.

AJ McCarron, QB

The Bills signed AJ McCarron, who played the past four years for the Cincinnati Bengals. Here's a closer look at the signing:

Grade: A. McCarron might not have the same experience as some of the other bridge quarterbacks on the market, but he offers more upside and presents tremendous value at only $10 million over two years with $6 million guaranteed.

What it means: This week has been a game of musical chairs for free-agent quarterbacks and teams with openings at the position, and McCarron and the Bills were perhaps the last potential match remaining. While the Bills were never considered suitors for Kirk Cousins, it is unclear whether McCarron was their first choice to fill the veteran role at quarterback or whether there was legitimate interest in Buffalo in Case Keenum, Sam Bradford, Teddy Bridgewater or others who signed elsewhere this week. In McCarron, the Bills get some upside that would not have come with signing an available remaining veteran such as Matt Moore or Derek Anderson. McCarron or not, expect the Bills try to trade up and draft a quarterback in April. The best case scenario for Buffalo is McCarron blossoms given a chance to start and the Bills are able to develop a drafted quarterback behind him, giving McCarron some trade value next offseason.

What's the risk: This is a two-year deal for McCarron, which reflects how he is likely viewed as a bridge option to a younger quarterback. There is little financial risk to the Bills, who could release McCarron with only $2 million in dead money after the 2018 season. The Bills are getting far from a sure bet in McCarron, who has made only three career starts, all in 2015. He will not bring the same graybeard presence to the quarterback room that the Bills might have gotten in Josh McCown, Anderson or Moore. If McCarron cannot turn his flashes of potential from 2015 -- a 66 percent completion rate, 97.1 quarterback rating, six touchdowns and two interceptions -- into results this season, there might be questions about whether the Bills should have kept Tyrod Taylor on a one-year, $18 million deal instead of trading him to Cleveland for a third-round pick. However, the Bills are getting a bargain in McCarron. He has only a $3 million cap number in 2018, meaning the Bills saved $7.44 million in signing McCarron, trading Taylor and taking a $7.64 million dead-money charge for him this season.

Trent Murphy, DE

The Buffalo Bills have agreed to a three-year, $21 million deal with Trent Murphy, who spent the past four seasons with the Washington Redskins. Here's a closer look at the signing:

Grade: B. The Bills are upgrading their pass rush but it will come at a cost, as Murphy becomes one of the team's highest-paid players.

What it means: Defensive end was considered an under-the-radar need for Buffalo despite having former first-round pick edge rushers in Jerry Hughes and Shaq Lawson. The Bills pressured opposing quarterbacks on 24 percent of pass plays last season, the second-lowest percentage in the league, according to ESPN Stats & Information. Hughes recorded only four sacks last season, his lowest total since 2012, while Lawson has generally been disappointing since being drafted by then-coach Rex Ryan and general manager Doug Whaley in 2016. When Lawson missed time last season because of leg and ankle injuries, the Bills struggled to get consistent pressure on quarterbacks from backup defensive ends Ryan Davis and Eddie Yarbrough. This signing could help fix that problem.

What's the risk: Murphy's deal is for three years at $21 million, making him the Bills' fifth-highest-paid player in terms of average salary per season, although it is possible that defensive tackle Star Lotulelei will exceed that number. The Bills are betting that Murphy can return to form after missing all of last season with a torn ACL. Murphy had nine sacks in 2016, playing entirely as a reserve for Washington. He will be paid starter-level money in Buffalo and must be an effective pass-rusher for the deal to be worth it. This is a gamble by the Bills.

Kyle Williams, DT

The Bills re-signed Kyle Williams, who has played the past 12 years for Buffalo. Here's a closer look at the signing:

Grade: A. As long as Williams can maintain his level of play at age 35, this is a solid re-signing that will maintain some continuity of leadership in the locker room from last season's playoff team.

What it means: Second-year Bills coach Sean McDermott spoke at the combine about how it is sometimes difficult to carry over the culture and success of one year into the next. McDermott witnessed that with the Carolina Panthers, who went 15-1 and made it to Super Bowl 50 in 2015 before dropping to 6-10 in 2016. Of the Bills' five team captains last season, McDermott has already lost two this offseason: center Eric Wood, who is retiring because of a neck injury, and quarterback Tyrod Taylor, who was traded to Cleveland. The Bills could have lost a third in Williams, but his decision to continue playing and re-sign with Buffalo means he will return as the team leader next season. Guard Richie Incognito noted last season that players told McDermott to keep his pregame speeches brief and turn it over to Williams. The stalwart defensive tackle's speeches will return in 2018.

What's the risk: Williams' one-year deal is worth up to $6 million with $5 million fully guaranteed. That means his cap number will be less than it was the past two seasons ($6.25 million in 2016 and $8.3 million in 2017), which is a fair adjustment given Williams will become the seventh-oldest defensive player under contract for 2018 in the NFL. Williams was the 51st-ranked interior defensive lineman in the NFL last season by Pro Football Focus, and with 3.0 sacks last season, he was not as statistically productive as he was from 2010 through 2016, when he made five Pro Bowls. Even so, he is a far better starting option alongside soon-to-be-signed Star Lotulelei than any of the other defensive tackles on the Bills' roster. Buffalo could still use the draft to find Williams' eventual successor.

Star Lotulelei, DT

The Bills are expected to sign Star Lotulelei, who played the past five years for the Carolina Panthers. Here's a closer look at the signing:

Grade: B. Without knowing the details of Lotulelei's five-year deal, it is hard to say whether the contract was worth it, but Lotulelei fills a position of desperate need for Buffalo.

What it means: The Bills will open about $15 million in 2018 cap space with their trades of quarterback Tyrod Taylor and left tackle Cordy Glenn, which allowed them to make a bigger splash in the free-agent market. Lotulelei fills what was the Bills' biggest need outside of quarterback: a gap-clogging defensive tackle who could help shore up the run defense. After trading Marcell Dareus to the Jacksonville Jaguars last October, the Bills allowed a league-high 18 rushing touchdowns and an AFC-worst 1,487 rush yards, according to ESPN Stats & Information. Of those yards, 1,105 were inside the tackles, and opponents' 4.8 yards per rush inside the tackles was tied for worst in the NFL. 2016 third-round pick Adolphus Washington filled in for Dareus and was ranked 113th among NFL defensive tackles by Pro Football Focus. Lotulelei's signing should not close the door on bringing back soon-to-be free agent Kyle Williams, whose playing style could fit the currently vacant defensive tackle spot next to Lotulelei.

What's the risk: While Washington was graded poorly by Pro Football Focus, Lotulelei was not considered much better by PFF. He ranked 109 out of 122 defensive tackles, including a poor 48.3 grade (out of 100) against the run. However, the Panthers ranked third in the NFL in rushing yards allowed per game (88.1) last season. If Lotulelei did not perform well, Carolina's run defense did not suffer because of it. Moreover, Bills coach Sean McDermott should have a strong idea of how Lotulelei fits into his defensive system after coaching him for four seasons (2013-16) as Panthers defensive coordinator. This is Lotulelei's first time as a free agent, but because he turned 24 as a rookie, age is a borderline concern. He will turn 29 in December and will be 33 by the end of the deal.

Chris Ivory, RB

The Buffalo Bills signed Chris Ivory, who played the past two years for the Jacksonville Jaguars, on Tuesday. Here's a closer look at the signing:

Grade: C. Between Ivory's age (he turns 30 this month), his cost ($5.5 million base value over two years) and his production in Jacksonville, there are reasons to be skeptical about this signing for Buffalo.

What it means: Bills general manager Brandon Beane made it clear last week he was seeking a power running back to complement the shifty LeSean McCoy, and Ivory falls into that category. Buffalo did not receive ideal production last season when that role was filled by Mike Tolbert, who will soon become a free agent. Yet Tolbert still posted a better average (3.7 yards per carry) last season than Ivory, whose 3.4 yards per attempt was the worst mark of his career. Although Ivory is almost three years younger than Tolbert, between McCoy and Ivory, the Bills now have two of the NFL's six oldest running backs who are under contract for 2018.

What's the risk: Beane told WHLD-AM last week that he could either fill the complementary running back role through free agency or the draft. Given Ivory received $3.25 million guaranteed from Buffalo, it appears running back will not be high among the Bills' draft priorities. The Bills are betting that Ivory can turn his career around after a rough stint in Jacksonville, which would be rare for any running back 30 or older. Buffalo looks to have the NFL's oldest backfield in 2018 with no immediate plan for the future. McCoy has the third-most career rushing attempts (2,185) of any running back under contract for 2018, and Ivory has the eighth most (1,112). Splitting carries might help keep both players' mileage down, but age is an undeniable concern at this position for Buffalo.

Vontae Davis, CB

The Buffalo Bills signed Vontae Davis on Feb. 26, who played the past six years for the Indianapolis Colts. Here's a closer look at the signing:

Grade: B-plus. Davis is four years older than E.J. Gaines, who he is projected to replace in Buffalo's secondary, but comes at a more reasonable price tag.

What it means: Davis, who turns 30 in May, is projected to start opposite promising second-year cornerback Tre'Davious White. The Bills gave Davis a one-year deal with a $1.5 million signing bonus, a $2.25 million base salary ($2 million of which is fully guaranteed) and a $250,000 workout bonus. He can also earn up to $750,000 in per-game 46-man roster bonuses, $250,000 in per-game 53-man roster bonuses and up to $3 million in playing-time incentives. The base value of Davis' deal is $5 million, which ranks 23rd at his position. If Davis can shake off a 2017 season shortened by groin surgery and return to his Pro Bowl form, he will be a bargain for the Bills. The signing has the added benefit of not factoring into the compensatory draft selection formula, giving Buffalo a better chance at securing an extra 2019 pick for its potential free-agent losses this offseason. Davis does not count as an unrestricted free-agent signing for Buffalo because he was released by his former team, the Colts. The Bills signed too many unrestricted free agents last offseason compared to those they lost, preventing the team from receiving what likely would have been a 2018 third-round compensatory pick for losing cornerback Stephon Gilmore.

What's the risk: Speaking at the NFL combine, Bills general manager Brandon Beane did not close the door on re-signing Gaines, who started 11 games last season and was Pro Football Focus' 13th-ranked cornerback. But it hard to see Gaines, who could command a deal in the range of $6 to $8 million per season, returning to Buffalo without a starting role. In choosing Davis over Gaines, the Bills might be getting a more durable player but are also getting older at the position without finding a long-term starter. Cornerback will be an under-the-radar need for the Bills in the draft, where Beane believes there is a deep class of prospects in the secondary.